H22 improvements

[CAUSHN]

HI peoples just wanted to know if anyone had any ideas on what some simple additions i can make to my H series engine but still keeping it N/A

Cheers

[curtis265]

http://www.attackforums.com/showthre...&threadid=1110

Disclaimer:
I just want to preface this by saying that I am not a professional mechanic or tuner, and that anything you take from this or do is at your own risk. I always strongly recommend getting information from multiple sources (not taking any one person’s word as gospel) and drawing your own conclusions as to what’s best for you and your car. All of that said, I’ll do the best I can to present logical & accurate information, and not lead anyone astray.

This series of posts will focus on upgrades aimed at the owner who is DIY oriented, willing to do their own research on the specifics of each job/modification, and interested in improving the H22’s power, driveability, reliability, and “fun-to-drive” factor - while keeping it naturally aspirated (no nitrous or forced induction). Many of these items will apply to those of you using the Accord’s SOHC F22 engine as well. For that matter, most of the principles should apply to any engine – there’s nothing particularly earth-shattering about any of this stuff.

First off, I highly recommend obtaining a Helms service manual if you plan on doing anything at all with this engine. They’re not cheap ($60-70), but anyone who has one will tell you it was the best investment they’ve ever made for their car. Every so often you can find used ones on eBay or the classifieds section of preludeoneline.com – which is another worthwhile investment. Membership to www.preludeonline.com costs $6 a year, but given the excellent writeups & knowledgeable member base, it’s well worth it in my opinion.

This installment will focus on basic maintenance and reliability modifications that I believe every owner should do. As I get around to it, I’ll post subsequent parts that will deal with modifications in increasing complexity/expense.

Basic Maintenace I – oil:
Contrary to popular belief, engine oil does not need to be changed every 3,000 miles. This might have been the case in 1973, but modern oils have come a long way in the past few decades. A quality conventional (dino) oil won't break down for at least 5,000 miles – and a good synthetic like Mobil1, Motul, Redline, or AMSoil will have no problems lasting up to 7,500 to even 10,000 miles or more (AMSoil actually advertises 25,000 mile drain intervals for their synthetics). If you don’t believe me, spend some time over at www.bobistheoilguy.com and send some oil samples of your own off to www.blackstone-labs.com.

Exceptions are always going to exist of course – like a turbocharged engine will require more frequent oil changes due to the extra heat of the compressor, as well as engines that see a lot of time just sitting around – no matter what the mileage, if you’re current oil’s been in there for 6 months, it’s time to change it. If you end up garaging the Attack for the winter, you’ll want to change the oil just before you put it away, and then again before you start it up for the summer.

It is imperative, however, that you change the oil filter religiously – the frequency will depend on the quality of your filter, but 5,000 miles is a good starting point. I change my AMSoil filter every 7,500. I use the AMSoil 10w30 synthetic as well – with a $20/year preferred membership, it’s no more expensive than Mobil1, and it outperforms it in many categories.

However, the H22 has an unfortunate habit of eating it’s oil – consumption can range from a quart every 1 to 5 thousand miles. Occasionally this is due to bad piston rings or valve seals, but even with engines in tip-top stock condition, the issue persists for almost everyone. Luckily, there’s a few inexpensive things that can be done to help the situation.
Cam Seal:
First, the intake cam seal on the distributor (passenger) side of the head is a POS. Just about every DOHC Honda engine I’ve ever seen eventually will seep some oil from this location. To fix it, STR, Golden Eagle, and AEBS all make a replacement seal which costs like $20-30. I got my STR one off eBay for like $21 shipped. There are some good how-to’s to be found on sites like www.preludeonline.com & www.honda-tech.com, but replacement is very easy – remove the valve cover (just like you would for a valve adjustment, see below), remove the camshaft holder plate & end cap, and replace the stock “seal” (I use the term loosely) with the new piece & some Hondabond or high-temp RTV. The replacement part has 2 or 3 rubber o-rings that will actually seal the location & keep it from leaking (versus the stock plastic piece, which has none . . . .). Also, make sure to follow the correct torque procedure & specifications when bolting the camshaft plate back down – basically just work from the inside out & torque the main bolts to 19 ft/lbs. It’s outlined in the Helms pretty clearly.
Oil Catch Can:
The second item for oil loss deals with the PCV system (positive crankcase ventilation). In stock form, there is a hose that supplies fresh air to the valve cover from the intake piping, and a second hose where excess fumes & vapors are sucked from the valve cover into the intake manifold. The PCV valve mounted at this location is there to ensure that flow only goes one way through the system. The problem is that on hard acceleration @ high rpms, engine oil is slung around enough up there to get past the valve cover baffles & enter the PCV valve – where it proceeds to get sucked into the intake manifold, resulting in a black sticky mess inside your manifold, and an impressive smokescreen coming out the tailpipe. Along with needing to add oil more frequently as it gets burned up, having it mixed in with your air/fuel reduces the effective octane, making detonation more likely.

The solution is to use an oil catch can. These are common (and necessary) on forced induction engines where more pressure exists in the crankcase, but are useful in n/a applications as well. It’s placed inline between the PCV valve & intake manifold, and intercepts any oil trying to make it’s way through. And at the same time, it continues to allow the crankcase to vent itself into back into the engine – so it should technically be able to pass a visual smog inspection since it’s a closed system & maintains the stock function. But be warned, there is a frightening amount of misinformation out there on how the PCV system works in stock form, and how to properly set up a catch-can system. What follows here are guidelines for the most logical & inexpensive system that I was able to come up with after several months of research.

Note – I’m still working on this section. As soon as I finish installing the catch can on my own car, I’ll finish it & post it up here. . . .

Basic Maintenance II – valve adjustments:
The H22 (like all Honda engines) uses solid lifters in the valvetrain instead of the hydraulic ones which are more common these days. The advantage of solid lifters is that they’re much more reliable at high rpms & less likely to float the valves. The disadvantage is, of course, that valve lash needs to be adjusted for proper clearances periodically. Honda recommends that this be done every 60,000 miles. If you run the engine fairly hard or in a variety of temperatures, it’s advantageous to do it at every 30,000.

Luckily, it’s not all that tough to do (despite what some dealers will lead you to believe) – there’s a great writeup on it over on preludeonline. It can be done with just basic tools & some feeler gauges, but the job goes much quicker using the recommended Tappet Adjuster & Locknut tools – they’re not all that expensive, so go ahead & pick them up. Just make sure to do your adjustments when the engine is cold (<100 degrees) & check clearances several times to make sure you’re getting an accurate reading.

Along with basic hand tools (socket set, pliers, screwdrivers, torque wrench), you’ll need some Hondabond or high-temp RTV to seal things back into place, and possibly a replacement valve cover gasket (depending on the condition of your original one). Just a note of caution – go very easy when you’re bolting down the valve cover – it doesn’t take much effort at all to strip those valve cover studs. The Helms manual lists a torque spec of 8 ft/lbs. on them, so go as easy as you can on them. They’re easy to replace should you bust one (you just need a 10mm deep socket), but $14 a stud from your local dealer can add up – plus a dealer will rarely have any parts for the H22 in stock, so you’ll have downtime waiting for the stuff to come in.

And if you like, you can try setting clearances .001 or .002 thousands tighter than the recommended specs – you might get a tiny bit more power, and many people report less valvetrain noise as a result. But if you do this, it’s even more important that you get in there & check the clearances on a regular basis – you don’t want them ending up too tight, or you’ll burn out valve seals pretty quick.

Auto -> Manual timing belt tensioner:
The last thing I’m going to talk about for reliability on the H22 doesn’t really qualify as basic maintenance, but is important enough to address right off. The auto-tensioner that comes on the H22 has a deserved reputation for failing. The unit relies on oil pressure within itself to keep tension on your belt. When it fails you’ll hear your belt start to flap around – and it won’t be long after that before the belt breaks & you’re out several thousand dollars for new pistons & a head rebuild.

Honda makes an updated version of the auto-tensioner which is supposedly more reliable, but it’s still a tricky piece to install & use correctly. A popular upgrade (especially for those who are running stiffer valvesprings, higher compression, or forced induction) is to use the manual tensioner which is found on the H23 engine (Prelude Si, ’92-96). I won’t go into the details on how it’s done, as there is a pretty good writeup on the process in the “how-to” section over at www.collectiveracing.net. You have to register in order to read the article, but it only takes a few minutes. Anyway, I highly recommend looking into swapping to a manual tensioner if it’s ever convenient (like at the same time you’re changing the timing belt & water pump – i.e. before you install the engine . . . .) And if you reuse your H22 balance shaft pulley, updating to a manual tensioner is actually less expensive than a new auto one . . . . about $90 in parts/shipping through an online supplier like Majestic Honda.

Relevant Links:
www.helminc.com
www.preludeonline.com
www.honda-tech.com
www.bobistheoilguy.com
www.blackstone-labs.com
www.amsoil.com
www.redlineoil.com
www.ltbmotorsport.com/motul.html
www.mobil1.com/index.jsp
www.collectiveracing.net
www.hondaautomotiveparts.com

[curtis265]

http://www.attackforums.com/showthre...&threadid=1121

Honda does an amazing job of extracting lots of power from their small powerplants, so don’t expect to find whopping improvements by doing these little modifications. But there are a few things that you can do to help power and consistency that are relatively painless (both labor-wise & financially).

Throttle Body coolant bypass & Fast Idle Valve block/removal:
From the factory, the H22 is set up so that coolant runs through the IAC and fast idle valves located on the intake manifold & throttle body. In cold weather, this helps the engine warm up to operating temperature more quickly since it controls your fast idle valve on the bottom of the throttle body. And in extremely cold weather (like 40 below zero or even colder), it prevents the throttle body from icing over as a result of the frigid air rushing through it. But once the engine is warmed up, all this feature does is help heat your intake charge. No, thanks.

Once again, I direct you to the FAQ section of www.preludeonline.com for a good writeup on how to do it – you’re basically rerouting the coolant lines into a circle to dodge the throttle body & intake manifold, and then blocking off the fast idle valve so you don’t end up with a surging idle because of it.

Again, it’s worth mentioning that this modification may not be desirable in extremely cold climates, as the car will take slightly longer to warm up since the fast idle feature is compromised. Although I’ve had it done on my car through the worst of NH winters with no ill effects, and no noticeable increase in warm-up time. On exceptionally cold mornings the engine may stall a second or two after I crank it up for the first time, but that’s it. Also, if a smog technician spots the change, he/she may not like it very much (not that it has anything to do with emissions, but you never know what they’ll take offense to).

EGR block plate:
I should mention right off the bat, that doing this will cause your car to throw a CEL (check engine light) if you’re using an OBD2 system. And this is one that definitely will not pass a visual smog inspection if it is noticed, and will reduce the chances of you passing a sniffer test as well.

The EGR (exhaust gas recirculation) is an emissions feature that Honda uses that isn’t particularly desirable in a performance engine. Basically, at certain load conditions & rpm, the engine routes a small amount of exhaust gas from the head back into the intake stream – the concept being that it’s giving any unburnt fuel another chance to go through the engine. By blocking it off, we’re once again keeping the intake charge cooler & cleaner for more consistent power.

Again, there is a good write-up on preludeonline.com that details the process, but it’s pretty simple – just remove the EGR valve (2 10mm bolts), and cut out a small plate to block off the holes. Then install the EGR in place over the plate so it will pass a cursory visual inspection & you can plug in the appropriate wiring harness & vacuum tube to keep the ECU happy. But after a couple cycles you will still have a CEL show up unless you do the . . . .

OBD2 “workaround”
This is a modification developed by the NTPOG (Northern Texas Prelude Owners Group). What the “workaround” does is modify (aka cut) the power wire to the long-term memory portion of the ECU. So every time you shut off the car, the ECU is effectively reset (without losing your clock & stereo settings). This is of most use for preventing emissions related CEL’s from showing up (like if you’ve done the EGR block modification, or decide not to run a cat).

I direct you to www.ntpog.org for instructions on how to do the modification itself. Although it’s possible to just snip the wire & call it a day, I strongly recommend following their suggestion of installing a switch that can be used to turn the workaround on & off – that way it can temporarily be set back to the stock arrangement for the purposes of tuning or diagnosing a CEL (it’s difficult to diagnosis a trouble code when the memory clears itself every time you shut down the car).

It should be mentioned, however, that doing this modification will have an effect on your air/fuel ratios until the ECU tunes the long-term fuel trim to where it should be. Basically, the Honda computer is designed to adjust it’s parameters by looking at the air/fuel ratio while running in closed loop operation (using the O2 sensor to adjust for rich/lean, etc.). This process only takes a few minutes once it's warmed up, but until that happens your fuel maps won't be quite where Honda intended them to be. The usual result is poorer gas mileage for the first few minutes of operation, a rough idle, and occasionally an excess of soot coming out the exhaust (the computer starts off somewhat rich, and will gradually tune itself to a leaner more efficient condition).

Ground Wires:
Like the other modifications in this category, it’s unlikely that you’ll see much improvement from upgrading your engine’s grounds unless the stock grounds are in very poor shape, or you’re running a highly modified engine. But as long as you don’t go with a “kit” (waste of money for $90 or $100), it’s inexpensive enough to be a worthwhile upgrade. They'll look nicer than the stock ones, and are a good way to make sure your ignition & electrical systems are getting all the power they need.

All you need is some 4-gauge power wire, ring terminals, and a new negative battery terminal clamp that can accommodate the larger wire. www.knukonceptz.com is an excellent online source for good inexpensive wiring, and the rest can easily be supplied by a local stereo shop, hardware store, or a site such as www.cardomain.com. All told, it can cost as little as $20 if you already have a decent crimping tool.

I’ve seen some people go hog-wild & add like 8 or 9 new grounds all over the engine bay (Exhibit A). This certainly won’t hurt any, but it’s definitely overkill & not necessary. I’d just find as many stock engine ground locations as you can (there’s 3 or 4 of them), upgrade them with your new wire, and make sure the grounding points are clean & tight.

Again, if you find more than 2 or 3 horsepower via your grounds I’d be surprised, but it’s an easy enough job to fall in the “why not?” category with the others here. And again, they look pretty . . . .

Hondata Heatshield intake manifold gasket:
Sometimes called a phenolic gasket, this is a modification that stretches the limits of the “cheap/easy” category, but I think is well worth it. Hondata makes an intake manifold gasket for the H22 which costs about $60. It’s made out of a thick high-temp plastic which insulates the intake manifold from the engine block and keeps it an average of 40-50 degrees cooler. A cooler manifold means a cooler intake charge - and a cooler intake charge, of course, means more power. Engines with the gasket have been dynoed at increases of 5% across the board as a result of the consistently cooler charge of air available.

Although the part itself isn’t all that expensive, the labor required to install it is frankly a PITA. Getting the intake manifold off while it’s on the car requires a wide assortment of sockets, wrenches, u-joints, extensions, pliers, screwdrivers, swear words, and band-aids. You’ll also need a stock replacement gasket for the one that goes between the upper & lower manifold sections, and possibly a new throttle body gasket as well (although usually the TB one is in perfect shape and can be reused). Again, there’s some pretty good instructions on how to go about it over on preludeonline. Of course, doing it with the engine out of the car would be eleventy billion percent easier & probably turn this into a 1/2 hour job.

Polyurethane motor mount inserts:
Energy Suspension makes these little suckers for about $35 for the front & rear, and do wonders at keeping the motor in check inside the engine bay. Advantages include less wheel hop, cleaner shifting action, and crisper response on accel/deceleration. The disadvantage is that they’re stiff enough to cause some vibration at the stock idle. Certainly not as big a deal on a car like the Attack as it might be on a daily driver, though. You can either raise your idle some, or just enjoy your new back massager. The front inserts are quite easy to put in, the rears are more annoying. But again, total cake if you install them during your initial engine installation.

Balance shaft disablement:
The H22 uses twin balance shafts to counter-act second order vibrations (vibrations caused by the connecting rods moving back & forth). This is purely a creature comfort, and although I haven’t tried it myself, I’ve read numerous reports that the extra vibration is almost negligible. General automotive lore is that a 4-cylinder engine over 2 liters in displacement will probably want balance shafts, anything smaller and the 2nd order vibrations are basically undetectable. Of course, there are quite a few other variables such as rod length, stroke, reciprocating weight, etc. But the H22 is only a few cc’s (157) over the 2 liter rule of thumb, so not a huge difference . . . . And FWIW, the new F22c (the ‘04 S2000 engine) has the exact same bore & stroke as the H22, and Honda didn’t feel it was necessary to equip it with balance shafts.

Disabling them is as simple as removing the balance shaft drive belt – once again, very easy to do with the engine out of the car & very time consuming to do it with it installed (it’s underneath the timing belt cover).

The only back-to-back dyno that I’m aware of was on a pretty heavily modified engine (bored out, high compression, big cams, headwork, all the bolt-ons, etc.), and it showed an improvement of about about 2 ft/lbs. of torque across the upper rpm range - so don’t expect this modification to throw you back in your seat. Some people claim it’s worth up to 8 or 10 horsepower, which I’ve always found very hard to believe – the things possess virtually no inertia, and rotate almost effortlessly on their bearings.

If you’re looking to save a little weight (as everyone should be), another option is to remove the shafts completely, plug or spin the inner bearings so you don’t lose oil pressure, & plug up the holes in the block you’ve left behind. Here's a pretty good little writeup on Honda-tech that covers what you'll need to do after you remove them. The shafts only weigh about 4 pounds each, but hey, every little bit helps. And if your oil pressure goes up slightly as a result, well, that's never a bad thing . . . .

Exhaust manifold insulating wrap:
Hot exhaust flows better – so if you can keep the heat from dissipating into the surrounding components, power will improve. And of course, there are lots of things under the hood that perform better & last longer if they’re not subjected to as much heat (alternator, battery, wiring, vacuum tubes, radiator, anything intake related, etc.). Header wrap isn’t particularly attractive or fun to install, but it can really help insulate the exhaust system & keeping that heat going out the tailpipe instead of baking your engine bay.

The more aesthetically pleasing (and expensive) method would be to utilize the services of a company like Jet-hot or HP coating . . . They specialize in applying highly attractive insulating finishes for headers, tail pipes, whatever you want. They claim that their coating reduces surface temperatures by more than 50%, and it looks great. Pretty slick.

Relevant Links:
www.preludeonline.com
www.ntpog.org
www.knukonceptz.com
www.cardomain.com
www.hondata.com/heatshield.html
www.energysuspension.com/hon1.html
www.honda-tech.com/zerothread?id=503372
http://www.jcwhitney.com/webapp/wcs/...&storeId=10101
www.jet-hot.com
www.hpcoatings.com/exhaust_coatings.htm

[curtis265]

part 3 seems tobe missing :S

[curtis265]

http://www.attackforums.com/showthre...&threadid=1133

Reliability & Strength:
For the most part, F & H series transmissions are pretty damn strong. On a naturally aspirated application, you’re not going to be seeing anywhere near enough torque for the raw strength of the transmission to become an issue.

However, like most modern trannies on the road, the synchros will rarely last very long if the box sees any abuse (speed or power shifting, etc.). And there is an issue with the 5th gear/reverse shifter fork – basically a product of a poor design. If it gets bent, you’ll find that 5th gear starts grinding, and putting it in reverse can become difficult or impossible. There is a TSB available from Honda on the subject, but reports from people who have had it done are rarely positive, as the problem returns in a few thousand miles. For the nitty-gritty on whats actually happening, check out the writeup done by Marcucci in the General FAQ section of www.preludeonline.com.

Unfortunately, there’s little to be done to avoid the problem other than being careful with your shifts. And if you’ve got the notorious 5th gear grind, make sure to treat that shift like it's glass to prevent a problem with your reverse. But there’s really no need to slam your gears anyway, and even speed-shifting serves little purpose for the vast majority of your time in the car. The cable tranny on the H/F trannies isn’t quite as forgiving of a sloppy shift as the rod-actuated ones on most B series, and there are no affordable aftermarket replacements. So relax a little and take an extra .3 seconds per shift, and your tranny & synchros should reward you with a nice, long life . . . .

Clutch:
First off, just because clutch A has a higher torque capacity than clutch B doesn’t mean it’s the better choice. Put too hard of a clutch on your engine, and you’re just gonna end up with a dead leg & a car that’s obnoxious to drive. In fact, due to the Attack’s light weight, the need for an aggressive clutch is reduced even more. A “sport” one rated at a ~33% increase in torque capacity should be enough clutch to handle the hairiest of naturally aspirated motors – and the vast majority of boosted ones as well. In fact, unless your eventual goal is to put down numbers somewhere north of 220 whp, I would say an OEM replacement clutch will be plenty strong for an Attack. Exedy makes a stock replacement kit that costs around $100, most “sport” or "organic" ones (the ACT HD-SS & Exedy Organic to name a few) will cost somewhere in the $220-280 region.

Flywheel:
Upgrading the flywheel is an excellent way to make a dramatic improvement in the performance of your engine. The stock flywheel weighs around 18.5 lbs – this is inertia that the engine has to accelerate & decelerate every time you rev up & down. By reducing this inertia, you can gain a noticeable improvement in engine performance, especially in the lower gears. They also make rev-matching a lot slicker (throttle blips will only take a fraction of the time they used to).

Although it’s possible to have a machine shop simply lighten your stock flywheel for a small fee, I wouldn’t recommend this method. Not only are you taking the chance of weakening your flywheel to the point where it could become dangerous, but the majority of material that’s “easy” to take off is located at the center of the wheel, which is less effective at reducing the inertia of the piece.

So you’re looking for a piece made from either aluminum or chromoly, weights typically range from 8-12 lbs. – look to spend around $150 to $250 for one. Just make sure that whatever you get has the appropriate timing marks (TDC & 15 degrees BTDC), and that the teeth are beveled to match your starter properly (there were some a few years back that ended up chewing up people’s starters because they were cut to match the JDM starter, not the one that came in our cars). Fidanza, ACT, Clutchmasters, and XTD are some examples of common brands.

Limited Slip Differential:
The goal of a limited slip is just what it says – they limit the amount of slip from any one tire. In a standard open differential, power always try to follow the easiest path. So if one of your wheels starts spinning (like the inside tire in a corner), all of your available torque suddenly becomes dedicated to pulverizing that tire instead of propelling you down the road.

To avoid that sort of peg-leg performance you use a LSD – these have the task of locking the differential if one wheel begins spinning faster the other, while at the same time allowing the wheels to turn at variable rates to some degree (like they need to when you’re cornering). There are 3 basic classes of LSD’s: viscous, clutch, & helical (or torsen). A full comparison between these categories is beyond the scope of this article, but a quick search with your favorite search engine should bring up plenty of reading material. For the (non-ATTS) F/H series transmissions, we’ve got 3 basic options available to us – Honda OEM (helical), Kaaz (clutch), and Quaife (helical).

If you can find one, an OEM LSD-equipped tranny is a worthwhile option. They came on the S spec JDM Prelude and on a couple different performance slanted Accords that were available overseas. While it’s not as aggressive or noticeable a LSD as a Kaaz or Quaife, it gets the job done, and is certainly better than nothing. And if you can find one, the price is often pretty reasonable (usually +$300 to the price of the transmission it comes in). Of course, you’ll usually need to buy the entire tranny at the same time, which both simplifies & complicates matters. It’s simpler since you’ll be able to just swap in the entire LSD-equipped transmission for your old one. But, of course, you’re also spending more money for the tranny itself, and you may not always be able to recoup your expenses by selling your original one. But as a side benefit, a LSD equipped Honda tranny often comes with slightly more desirable gear ratios . . . see below for more details.

The other two aftermarket options (Quaife & Kaaz) run about $800-$900 before installation. They are both excellent units, but they aren’t cheap – and installation involves removing & pulling apart the transmission, which is not a simple affair. I would highly recommend finding an installer who has experience in installing LSD's in Honda FWD drivetrains for this type of job.

One product I haven’t mentioned yet is the Phantom Grip - a low-cost “alternative” to a limited slip . . . there’s not a whole lot of people out there that have tried it, but it seems like for every report I’ve read of someone installing one & it working well, I’ve read another one where it fragged up their differential beyond repair. Personally, those aren’t good enough odds for me to feel comfortable using one. So unless you’re using a throw-away tranny & have another one lined up ready to go, I recommend saving up the extra money to get a real limited slip.

Final Drive gear:
The stock final drive ratio on the H22 transmission is a 4.266:1 ratio – this is pretty aggressive, but some startling improvements in acceleration can be found by using an even higher one. Labor involves disassembly of the transmission to replace the stock final drive ring & pinion gear with the new piece. If you happen to be installing a limited slip differential, it would obviously be cost-effective to do both of these at the same time . . . .

For options, Prodrive is the only company I’m aware of that makes that make a final drive for the H/F series transmission – it’s a 4.71 ratio, and retails for about $1,250. Other companies such as Houseman Autosport will make a custom one for you for about $1,500.

So this obviously isn’t a modification for the faint of wallet, but an upgrade from 4.266 to 4.71 will grant you a ~10% increase in torque at the wheels in every gear, at every rpm – that’s a massive improvement. Of course, the downside is that rpm levels at every speed will increase by ~10%, and maximum speed in each gear will be reduced by ~10% (unless you raise your redline). For a daily driver, this may not be desirable for some. But for a weekend vehicle like the Attack, I say pile on the gearing . . . .

Alternate Honda gearboxes:
At last count, there are close to a dozen different F & H series transmissions that will bolt up to the H22. The majority of them (like the F-series ones) have a taller final drive ratio and won’t be a very desirable match with the H22’s power-band, so I won’t bother addressing them here. But there are a few gearboxes that were available in one model or another that have ratios that are slightly more aggressive than the standard ’97-01 5th generation USDM model (the M2Y4).

***transmission disclaimer***
Trying to find reliable information on the different tranny codes & gear ratios on these boxes is pretty hard. I’ve done the best I can to compile the available options & present accurate information here, but I wouldn’t be surprised if there are mistakes . . . .
M2F4: These came in the USDM 4th generation VTEC Prelude (‘93-96), so they would be the easiest one find in a local junkyard (although the car is still far from common). All it’s gears save for 2nd are slightly more aggressive, while second is a tiny bit longer. Frankly, my only complaint about the 5th gen's gearing is that 2nd is too tall already, so this box will only exaggerate that with it's shorter 1st gear
M2B4: This box came on JDM VTEC Preludes and has identical gearing as the M2F4 listed above, but it came with a LSD (note that the M2A4 variant did not).
U2Q7: Found in the European Accord Type R, this has a first gear that matches the ’97-01 box, but it’s 2nd through 5th are the tightest you can find on a stock tranny. It also came with a LSD. For a non-daily driven car (or one that sees little highway time), this would be my choice of trannies. They’re hard to find though.
T2W4: This came from the Accord Euro-R (a JDM model), and has gearing identical to the U2Q7 above, save for a more relaxed 5th gear that is the same as the ’97-01 model. The combination of good 1st gear placement, an aggressive 2nd through 4th, and a semi-relaxed 5th make it very desirable to enthusiasts – especially since it also came stock with a LSD. But they’re quite rare, so best of luck sourcing one.
T2T4: This came in the Accord SiR-T (the F20b engine). This box is kinda cool since it's 1st through 4th gear ratios are identical to that of the 5th gen Prelude we got stateside. The only difference is that it has a taller 5th gear which is nice for highway driving, and it has a LSD.
For my own purposes, I maintain a little excel worksheet in order to keep track of all the tranny codes and their respective gear ratios. So if anyone’s interested in more specifics than I have here, let me know & I’ll e-mail you the section that pertains to the H & F series transmissions.

[curtis265]

http://www.attackforums.com/showthre...&threadid=1126

So once you’re ready to move beyond the basic bolt-on modifications, many people will tell you the next step is to upgrade the cams/valvetrain and get some headwork done. I disagree with this.

If you’ve chosen your parts with care & they’ve improved airflow as intended, your engine should be pumping enough air over stock trim that your stock fuel & ignition maps will be pushed to their limits. The stock ECU is capable of adjusting fuel trim up to 30% richer or leaner than stock, which for a speed-density system is fairly flexible (there’s no MAF to physically measure the amount of air the engine’s pulling in). But once you reach the ECU’s limit to compensate for added airflow, it’s very unlikely you’re going to see much more power, no matter how many parts you throw at the engine. And there’s a good chance you’ll be compromising reliability as fuel maps & ignition timing become less & less appropriate. So before you go any farther, right now is the time to step up & tune the computer.

First, a few notes about Honda computers. Until the advent of the new K-series 4-cylinder engines Honda’s been using the past few years, the computers are not flash programmable. What this means is that the stock computer is notoriously difficult to “chip”. There are replacement “chips” available out there, but I would steer far, far away from them – they’re most often just a copy of the Mugen program that tweaks ignition timing, leans out the air/fuel mixture, and gets rid of the rev limiter and trouble codes. The chances that one of these generic chips will be a good match for your engine are very slim.

Options:
So with the goal of being able to tune specifically for your setup, there are three basic methods available. The first is by using a complete stand-alone system. Examples of these are Microtech, Force EFI, Haltech, Motec, & TEC. These replace your entire computer & wiring harness with their own components. Their flexibility is endless, but they are notoriously difficult to install & tune. Just getting the engine to run at all can take a lot of time, although some have base maps available for different engines & setups which can speed up the process. The listing of stand-alones above is by no means comprehensive, so you’ll have to check around yourself if you’re in the market for this type of system.

The second group of engine management systems are what I call “intercept” systems. The AEM PMS, EFI systems, Zdyne, Greddy e-manage, and Apexi VAFC all fall into this category to varying degrees & extremes (although one could argue that the AEM one belongs in the stand-alone group). Basically these work by intercepting the stock sensors at the ECU, and modifying the signals (or supplying it’s own) to suit it’s own purposes. This is a fairly popular technique, as it often allows the Honda ECU to continue controlling all the countless periphereal functions that can be so tedious to set up & get working properly on a full stand-alone. Once again, there are probably systems available in this group that I neglected to mention.

The third group really only has one player – Hondata. This is the only company that has devoted the R&D to actually hacking the Honda programming, and supplies the hardware & software to dyno tuners & end-users so they can write their own chips. However, Hondata doesn’t support all Honda ECU’s – most notably, they’re unable to work with OBD2 computers. So an OBD1 computer & conversion harness will be necessary if your engine is OBD2. Nor does Hondata support the H series ECU’s – not enough demand to bother figuring out it.

But any OBD1 ECU from a VTEC Civic (P28) or Integra (P72) is capable of running the H22 given the proper fuel & ignition maps. Just make sure to read up on any features you might lose by going to the P28 or P72 (like the knock sensor or IAB’s). Personally, I think the P28 is the best option – it’s way more affordable than the P72, and even though you lose knock sensor & IAB support, IAB’s can be controlled via the nitrous actuation function that comes with the Hondata setup, and there are more accurate ways to control the knock sensor . . . . .

Knock Sensor:
Now, the stock H22 comes with a knock sensing system – the sensor is mounted at the back of the block, and below 5,500 rpms it protects the engine from pre-detonation by retarding ignition timing when knock is detected. This works fine for people with stock engines who put in 87 octane swill by accident, but we’ve now begun to modify the powerplant fairly far from it’s original parameters. I’ve read about quite a few cases where the stock knock sensor & ECU weren’t terribly pleased about all the new noises the engine was making, and started pulling ignition timing to try & rectify the situation when nothing was really wrong. This, of course, results in reduced performance, crappy throttle response, and an engine that bogs when you least expect it (all symptoms that are notoriously difficult to troubleshoot). Not to mention, many engine management systems don’t support the use of the factory knock sensor. So now is an excellent time to upgrade to . . . . a J&S Safeguard system.

This unit utilizes your stock sensor to control pre-detonation to an incredibly fine degree. While this may seem like overkill for what is basically just a bolt-on engine at this point, it provides the ability to tune your engine much more aggressively than you would (or should) be willing to try without it. For about $350-500, it’s peace of mind that’s not to be underestimated – especially if you have any intentions of tuning the car yourself.

Tuning:
Regardless of what engine management system you choose, it will require tuning for your engine to run properly & make good power. You can either get the name of an approved tuner in your area straight from the manufacturer of your engine management system, or better yet – choose your engine management system based on what your trusted tuner of choice is familiar with using . . . You can have the best engine management system & the most capable tuner in the world, but if he/she’s not familiar with the system, it’s not likely to be a very satisfying experience. Even in a best case scenario, be prepared to drop some semi-serious cash for access to dyno facilities & a technician (at least a half day’s worth of tuning, usually at $100+ per hour).

Although if you like to figure things out for yourself (a good bet if you've gotten this far . . . ), you can do a lot of the tuning yourself with a good wide-band O2 sensor & datalogging capability. A wideband O2 sensor is different from a standard sensor in that it reads 0-5 volts vs. the 0-1 volts a standard one puts out. This means the resolution is accurate over the entire air/fuel spectrum, and not just a narrow range like on stock sensors. Narrow-band sensors are fine for their intended purpose (keeping you as close as possible to 14.7:1 air/fuel during part-throttle conditions), but they’re notoriously inaccurate when your air/fuel ratios stray too far from stoichiometric. And for safety’s sake, at any kind of aggressive throttle position or load you’ll probably be tuning for a good bit richer than that (anything from 12-13.5:1, depending on your application). So in order to measure those richer air/fuel ratios with any kind of accuracy, you need a better sensor.

Wideband systems have recently started to become fairly affordable, due to the availability of a new Bosch sensor that only costs about $30 (comes stock on a couple new VW’s). To get an idea of the systems available to control this sensor, check out this thread over on Honda-tech.com. Full setups can now be put together for only a few hundred dollars, where as just a few years ago you couldn’t find one for under a grand.

With a good wide-band sensor set up & the ability to datalog, it’s possible to do all of your fuel map tuning on the street instead of spending long hours on the dyno (which quickly gets expensive). Street tuning is becoming more and more popular for enthusiasts, since real-life driving scenarios (part-throttle, light-load, tip-in, etc.) can be difficult to recreate in a dyno situation – or impossible on a common inertia setup like a dynojet.

And some systems (the AEM PMS comes to mind) even offer an “autotune” function that writes it’s own fuel-maps as you’re driving by using the wideband O2 sensor readings & a target a/f ratio (basically an advanced closed-loop setup). You still may need to hit the dyno to figure out what to do with your ignition maps, though – although it’s theoretically possible to tune those by yourself as well by using a combination of a G-sensing “dyno” (G-tech or an equivalent) and a J&S Safeguard for your safety net. Just make sure you have an appropriate place to do your tuning . . . . Non-residential, lots of space, and no traffic. It’s a rare neighbor that will appreciate you tuning full-throttle acceleration passes past their house . . . .

Relevant Links:
www.microtechefi.com
force-efi.com/fast.htm
www.haltech.com
www.motec.com
www.electromotive-inc.com
www.aempower.com/product_ems.asp
www.efisystems.com
www.zdyne.com
www.greddy.com/products/electronics.htm#eManage
www.apexi-usa.com/electronics_vafc.asp
www.hondata.com
www.jandssafeguard.com
www.honda-tech.com/zerothread?id=635792

[curtis265]

http://www.attackforums.com/showthre...&threadid=1196


Camshafts:
Camshafts are another way to increase the amount of air your engine can pull in, and at what point in the powerband it breathes the best. By altering the size & shape of lobes, it changes the manner in which the valves open, how your engine breathes, and consequently how/where it makes it’s power . . . The two specifications of lift & duration are basic indications of what sort of power-band you can expect out of the cam. However, the shape of the lobe has a big impact on power as well, and is too often neglected. Two cam grinds with identical lift & duration numbers can perform very differently . . . . Ramp angles & flow rates at different amounts of partial lift can make surprising differences.

Valvetrain:
Once you’ve decided on your cams, you’ll need to focus on the valvetrain necessary to support them – mainly the valve springs. They have the job of keeping the valve closed whenever the cam and rocker arm are not pushing it open. When you start running the engine at a higher rpm or at larger amounts of lift, the stock valvesprings will no longer be adequate – and the valves will begin to “float”, which means they’re not closing when they’re supposed to. This leads to all sorts of bad things . . . . burnt valves, burnt seals, carbon build-up, piston-valve interference, etc . . . .

However, there’s more to it than just using the stiffest springs you can find that allow for the lift you need. Remember, not all of the energy required to compress those stiff springs is gotten back from them, so you lose some accelerative ability with uber-stiff springs. More importantly, too-stiff springs means increased wear on your rocker arms, cams, and timing belt. So it’s a tricky compromise of using springs that are stiff enough to prevent valve float, but not so stiff so as to compromise long-term reliability. So if your desired cam profile requires the use of crazy stiff springs, you might want to look into the possibility of upgraded or hardened rocker arms.

Some companies that make camshafts & valvetrain upgrades for the H22 are Crower, Crane, Skunk2, Gude, JUN, & Webcams. And if you poke around some, there’s some good FAQ’s & articles to be found on the various websites that go into more detail on valvetrain design & theory.

Adjustable Cam Gears:
These replace your stock cam gears, and allow you to adjust intake & exhaust cam timing independently of one another. This gives you tuning flexibility since you can shift your powerband around to where it will do you the most good.

Compression Ratio – static vs. dynamic:
Most people are familiar with the concept of static compression ratio – the stock H22 comes in at 10:1 (10.6:1 for JDM models, 11:1 for S-spec). However, when all is said and done, knowing static compression ratio is only of use if you’re keeping the cam profiles completely stock. The reason for this is that your intake and exhaust valves are not necessarily completely closed when the piston starts it upward movement, which means some compression inevitably gets bled off before the valves close. And when you put a more aggressive set of cams in, that bleed time is increased even more. Since we’re now playing around with valve timing, we need to start referencing dynamic compression ratio which takes into account the cam profiles. Ultra-aggressive cam profiles aren’t going to make nearly as much power as they should when you keep the stock static compression ratio. For more details on this, there’s an excellent article (and links to a dynamic CR calculator) on www.team-integra.net (registration required).

So, bottom line, if you’re running hot cams, you need to raise your compression ratio to bring your engine’s efficiency back up. If you’re avoiding bottom-end work for the time being, this can be done in the head by a number of ways (thinner headgasket, milling the block/head, or even higher CR valves), but I wouldn’t try and gain more than .5 of static CR via any of those methods – and make sure to do your research so you know exactly what problems and/or conflicts may arise from them. In my opinion, raising CR by using more aggressively domed pistons is a far more desirable method, but that can be cost-prohibitive. But if you’re not going too far with it, a milled head or thinner headgasket can get you some good results on a budget. Just be prepared for some extra tuning on the dyno to get your cam gears set – by moving the head closer to the block, your cams will naturally retard themselves from their original/ideal timing.

Headwork:
Gone are the days when you can just pull off the head of your engine, fire up a die grinder, and buff out an extra 20 or 30 horsepower in an afternoon. Modern head design and casting techniques have improved so much it’s scary, and the heads that you find on cars these days (especially Hondas) are good. Very good. So given the extremely high baseline we’ve got to work with, it takes some awful careful work to improve on them. So it requires a true professional with access to some very expensive equipment. Grinders, flow benches, wet flow testing, CNC machines, etc.

All of that said, head porters are still managing to find a suprising amount of power lurking in Honda heads. You’ll find claims of 15-25 horsepower thrown around, but the exact benefits are going to be extremely sensitive to the amount of work you already have in the engine, or how much the stock head is now holding you back. On a completely stock engine I would be surprised to see more than 10 horsepower from competition quality headwork. Plus, the best headwork typically won’t have the highest peak horsepower gain . . . by going for a big increase in peak horsepower, one usually has to increase airflow so much that efficiency suffers at the lower & middle rpms, which means a sacrifice in power at those points. A more conservative job can retain more area under the torque curve, and the car will be faster for it. Making sure your head porter knows the goals & details of your setup before they get started is very important.

So by sending your head off to one of these places, you can expect to have a few things done to it. First and foremost, the head should get a thorough freshening back to new OEM quality - checking for straightness and wear, cleaning/degreasing, resurfacing, guides replaced if necessary, etc. And most importantly, all valve seals replaced with new OEM ones.

Second, the most advertised portion of the work, the port & polish. This is where the flow-bench comes in to make sure those shiny new ports actually are flowing more air than they did before . . . looks can be deceiving. Anyone who doesn’t use a flowbench to research and check their work is not to be trusted, in my opinion. The process involves not only deburring, smoothing, & shaping the intake & exhaust ports, but working on the combustion chamber roof & portmatching to the manifolds.

Third, maybe the most important portion of the headwork, the valve-job. Again, a flow-bench is vital to make sure work done here is actually helping, as well as a vacuum test to make sure you’re getting a good seal. The valve job can include a multi-angle seat cut for better flow, swirl polishing on the valve itself, all sorts of tricks to promote air/fuel flow & avoid condensation.

Really, the sky is the limit as to what you can have done. For example, if you’re going to be resleeving the block and boring the engine out a few extra millimeters, you’ll want some attention to be paid to the combustion chamber roof to work with the new bore diameter. Some head porters like to have the pistons on hand that you’ll be using so they can work the combustion chamber to function best with their specific shape – this is an excellent practice in my opinion. Playing with quench areas is another way to increase burn efficiency. If you’re running out of room for more lift and duration in your cams, you can oversize your valves to allow more air into the combustion chamber . . . on a stock bottom-end this isn’t likely to help you very much, but with an engine bored a few mm or aggressively domed pistons limiting valve lift, the extra breathing capability from larger valves will come in handy. And then you can get into exotic materials for your valvetrain . . . lightweight valves, lightened rocker arms, etc. – the less weight you’ve got up there, the easier your engine will rev and the less likely you’ll be to float a valve. Something else that can be done is to actually add material back into the combustion chamber - since deshrouding & polishing will increase the size of the combustion chamber, compression ratio will decrease. By strategically welding and shaping more material into the chamber, CR can be brought up to it's desired level, and flame propogation & exhaust flow can be encouraged even more. This, of course, requires extensive experience in welding aluminum, as well as combustion chamber theory and design.

You’ll also want to send in your intake manifold to get the full treatment as well. Even if you manage to find yourself a good aftermarket manifold, sending it in with your head is a good idea – at the very least they can be port-matched to smooth out airflow entry, and any stray casting marks or burrs should be removed. Like I mentioned in the bolt-on installment, lots of power can be found (or lost) in the intake manifold.

As far as who you choose to send your head to for work, that’s a topic that’s almost guaranteed for debate no matter who you talk to. Evidence as to how different companies headwork perform against eachother is practically impossible to find – back to back comparisons simply don’t exist. And if you look around, even the most reputable people have dissatisfied customers who are of the opinion that they’re total shams. So all I can suggest is that you do as much research as you’re able, and choose someone who you feel understands exactly what you’re looking for. Don’t take much stock in second-hand information or horror stories. If a shop or head-porter does work for successful race teams, that can be a plus - it indicates that they're trusted by guys with a lot at stake. But bear in mind that it's rare that your personal job will get the same amount of attention as the higher profile clients. And just because the shop advertises a 9-second drag car that's received their magic touch, it doesn't mean that your car will magically become just as fast if you send your head to them. If you can find people who’ve had direct dealings with a specific place, great – just remember to get the shop’s side of the story if it’s a bad review.

Someone who does good headwork will take into account everything about your project – what cams you’ll be using, what intake manifold, what pistons, your projected compression ratio, your desired powerband, what sort of emissions regulations you need to pass, etc. If those questions aren’t being asked (or they’re not interested when you tell them), the chances of getting work done that will complement your modifications are not good. A good shop should be understanding of the fact that you’re about to drop a fairly large quantity of money (anywhere from $800 to $3,000) on a service that isn’t reliably quantifiable, so they should be willing to spend some time talking things over with you. And get everything in writing . . . nothing works better to prevent misunderstandings & keep all parties honest.

For headwork, some of the available options to look into are:
Alaniz, DPR, Portflow, Endyn, RLZ Engineering, DH Racing, R&D, Gude, and JG Engine Dynamics.

[curtis265]

http://www.attackforums.com/showthre...&threadid=1321

On a naturally aspirated engine, there are 3 basic methods to increase it’s output. The first lies in making more power at higher rpms (with complimentary improvements in gearing), the second is improving efficiency (inertial, thermal, and volumetric), and the third is displacement. Building up the bottom-end can improve all 3 of those areas . . . By strengthening and lightening the bottom end (crank, rods, pistons), higher rpms become possible since the stronger components can withstand higher forces - and the lower weight of forged components reduces said forces as well. By increasing the compression ratio via pistons, thermal efficiency can be improved. By reducing weight & inertia, less power is lost turning the engine. And of course, with an increased bore or stroke, we get more displacement which allows the engine to ingest a larger amount of air/fuel.

Make no mistake, reworking the bottom-end is very intensive from a labor, equipment, and cost perspective. But if you're really looking to make some power, building up your bottom end correctly pays huge dividends - both on the dyno as well as reliability a few thousand miles down the road.

Pistons:
Forged aftermarket pistons offer several advantages over the stock pistons – namely durability, lower weight, and the ability to tweak compression ratio. Durability is pretty self-explanatory, forged pistons can just plain take more abuse. Weight is a big deal as well, since any weight lost off the pistons is weight that your engine doesn’t have to sling around. Towards the stock redline, pistons are moving at average speeds of up to 25 meters per second and changing directions more than 200 times a second, so a few grams can really make a difference in the amount of force that your rods and crank have to bear. And lastly, the ability to change your compression ratio can have a huge impact on power. As I discussed in the headwork article, once you start using big cams with lots of duration & overlap, dynamic compression ratio begins to plummet. So in order to keep thermal efficiency up, you need to increase the static compression ratio. Just be sure to triple-check all your clearances before you finish reassembling the motor – you’ll want to clay your engine to find out just how much space you’ve got to spare between your pistons and valves, and how much room for camshaft advance & retard you’ve got. Not doing so can have disastrous results down the road when you attempt to tune the cam gears.

Now, using forged pistons in the H22 has another little wrinkle – the stock sleeve liner material. Honda uses a material called “FRM”, which stands for fiber-reinforced metal, and it’s been heavily debated whether or not it’s possible to run forged pistons in the FRM sleeves. Along with a type of carbon fiber, FRM uses standard aluminum alloy as a major component. Since forged pistons are also aluminum . . . . any contact between the two is going to result in severely scarred cylinder walls, and an expensive rebuild. Now, there are companies that claim their pistons will work perfectly with an FRM sleeved engine (like JUN & Wiseco). However, I have yet to find any proof that this is the case (like an engine torn down & inspected after 30,000 miles or so of use). Bottom line, the number of engines that have been ruined by attempting it vastly outnumber the people that claim it works. So if you want to run forged pistons, plan on resleeving with some iron ductile sleeves – more on that topic in the section on increasing the bore.

My own personal conjecture is that it is possible to run forged slugs in the FRM sleeves, but it requires a combination of factors that I don’t believe anyone has worked out yet. With a piston of the proper (read: high) silicon content to limit expansion, correct clearances, modified sideskirt design, and probably some sort of coating on the piston, I think a forged set of pistons in the stock sleeves could have no interference or scraping issues whatsoever. But I really don’t believe anyone has found that right combination yet. However, both the NSX & S2000 use FRM sleeves & come stock with forged pistons (extremely high silicon, iron-coated), so it’s obviously not impossible.

If you're not interested in going with a full resleeve, a very viable option is to get a set of OEM Type S pistons. These aren't forged, but are attractive for a mild to moderate N/A build as they bump compression on a stock engine up to 11:1, and can be found for around $300 (including rings). And depending on the condition of your cylinders, you may not even need to rehone - but plan on one anyways.

Connecting rods:
Assuming you don’t need a custom length because of a moved wrist pin or lengthened stroke, there are several inexpensive (<$400) off the shelf options available. For a n/a build, you want to find as light-weight a rod as possible that has the strength you need – although most any aftermarket forged rod you can find will be plenty strong to handle the stresses a non forced induction H22 can place on it (assuming a reasonable redline, of course). Plus the more weight you can lose off the rods, the more inertia you’re going to free up. And if you’ve disabled your balance shafts, lighter connecting rods will reduce those secondary vibrations as well . . . .

Crankshaft:
The stock H22 crankshaft is an extremely good piece. Forged steel, fully counter-weighted and balanced right from the factory, you’d be hard pressed to find a superior unit without spending an obscene amount of money. It can, however, be lightened - it’s possible to take as much as 8 or 10 pounds off without sacrificing it’s strength or balance, which equates to a significant reduction in rotating inertia. You do not, however, need to “knife-edge” the crank – anyone who suggests this procedure is not familiar with how Honda engines operate, and I would recommend going elsewhere for advice. Knife-edging typically reduces the amount of friction, frothing, and windage resulting from the crank spinning through the oil bath. On a Honda engine, however, the crankshaft does not spin through an oil bath, so there is negligible windage to begin with. Therefore, there’s nothing to be gained by knife-edging it.

Bearings:
Again, the Honda bearings are extremely good. I’ve never encountered any evidence that supports the necessity of replacing them with aftermarket ones. On a full rebuild, you’ll want to check clearances to make sure they’re within spec, and replace if necessary. But as long as they’re getting proper oiling, and your engine is in a good state of tune, the bearings will take anything you can throw at them.

Oiling:
Prodrive makes an upgraded oil pump gear, and while this piece isn’t cheap by any means, it can be good insurance. Combined with improved reliability, it increases oil pressure slightly. On a street motor, I think it’s probably overkill – but if your engine spends a prolonged amount of time at high-rpms (aka track time), it’d be a worthwhile investment.

Increasing the bore:
While it is possible to bore out the stock sleeves on the H22, it’s not possible to go very far on them . . . . at all. In fact, the factory potential for overboring the stock 87mm is just .25mm, which will garner you a whopping 12cc’s (a 0.6% increase in displacement over the stock 2,157cc’s). On a budget rebuild (i.e. Type S overbore pistons & stock sleeves), this may be worthwhile as a “why not” modification, but don’t kid yourself about the amount of power you’ll see from doing it, aside from the increase in compression. If the improvement due to the extra displacement were measurable on a dyno, I’d be surprised.

In order to increase the bore a little more substantially, a resleeve is required. Resleeving the block needs to be done by a competent machine shop, and replaces the factory FRM (fiber-reinforced metal) sleeves with iron ductile ones. Some options available for resleeving include Golden Eagle, AEBS, Darton, and LA sleeve liners. A full-on resleeve will cost anywhere from $800 to $1,500, while replacement sleeve liners can be as little as $400 after labor. But bear in mind – stripping & shipping your block is a significant expensive just by itself.

Once resleeved, the bore potential is now only limited by the bore spacing and the size of your balls. While I’ve read of people going out as far as 91mm on the stock block, doing so leaves a laughable amount of material separating the cylinders. Even a 90mm bore is pushing the limits of reliability, and you can have trouble with the head gasket sealing properly between cylinders. For a streetable engine, an 89mm bore is probably as far as you want to go – or possibly 89.5, if you can find pistons in that size (I’m not aware of any off the shelf). With the stock stroke, an 89mm bore represents a solid 100cc more displacement, or an almost 5% increase. Assuming your top-end is up to the task of the extra flow, this theoretically gives you another 5% more torque across the board – nothing to sneeze at.

And if you’re boring out your cylinders, you may want to have a matching bore done on your head – a topic I touched upon briefly in the headwork portion of this series. This sort of deshrouding can take some finesse, as any material you take off the head is going to reduce your compression ratio – so I definitely recommend the advice of an experience engine builder/head porter if you plan on going this far with your engine build. Some builders don't recommend bothering at all, claiming that the gains from opening up the head bore are negligible compared to the amount of effort to do it correctly.

Here's an few articles on sleeving courtesy of Honda-central.com and Overboost.com. And here are a few links to some of the more popular sleeving companies for Honda blocks: Golden Eagle, Darton, and AEBS - another way to go that seems to have a good reputation is Dan Benson, but I'm unable to find a website for him. A search on honda-tech should bring up contact information, though. Another possibly more affordable option is going with LA sleeve liners - places like www.importperformanceparts.net use them.

[curtis265]

http://www.attackforums.com/showthre...&threadid=1321 part b

Increasing the stroke:
The stock stroke of an H22 is 90.7mm, and there are several (relatively) inexpensive ways to go about stroking it even further using Honda crankshafts if you're so inclined.

The F & H series blocks are all extremely closely related – so in many instances it's possible to use an F or H series crank in a different block. The only limitations lie in the change in crankshaft mains in 1998 – they went from a 50mm main to a 55mm main. The most common option for an H22 is to use the 95mm crankshaft from the H23 or F22. With the stock bore, this works out to 2,259cc’s of displacement – a 102cc increase (or 2,364cc’s and a 207cc increase if combined w/ an 89mm bore). An even more extreme crankshaft can be found in the F23 engine from some of the more recent Accords – it rings in at a 97mm stroke (2,306cc’s for the stock bore, 2,414cc’s on an 89mm bore).

But however much fun it is to dream about the vast amounts of displacement available via stroke, there are some serious considerations to make beforehand. By changing the stroke, you’re messing with some fairly vital engine geometries – namely bore/stroke & rod/stroke ratios.

Without delving too deeply into the physics of engine geometry, basically the length of an engine’s stroke (and the resultant rod length) is directly proportional to it’s ability to rev. Longer stroke = faster piston speeds. Shorter rod = faster piston acceleration, more side-loading, and less dwell time at TDC. As a result, the engine’s torque curve will want to move lower in the powerband (which can make any kind of aggressive final drive you’d like to use quite frustrating). Because of the increased piston speeds, do NOT expect to be able to rev to the stock redline w/out some seriously strong connecting rods & rod bolts. And even if your bottom end is physically capable of taking the abuse of the forces resultant of uber-high piston speeds, chances aren’t good of you making any power up there to begin with – at least, not without some hardcore headwork & massive camshafts. The longer your stroke gets, the harder it is to fill those cylinders efficiently. The shorter the rods, the more power you'll lose due to friction against the sides of the cylinder walls. At it’s extremes, the pistons will actually begin to move as fast (or faster) than the combustion’s flame front. There’s obviously not much power to be found in that scenario.

Another concern is that on the 95 & 97mm crankshafts, less care is taken from the factory in getting them balanced for higher rpm operation - although they're still very nice forged steel units, they're simply not designed to be spun at the kind of speeds the H22 was. So if you decide to use one of these cranks, some extra work balancing, polishing, and even cryo-treating for more strength would be in order.

One final reliability consideration is the oil squirters . . . The H22 comes stock with oil squirters aimed up at the bottom of the pistons. This helps cool the pistons and ensures proper oiling in the cylinder. However, when the move is made to a larger crankshaft, they may not fit anymore . . . which would hardly be desirable for sustained high-rpm operation.

As far as actual stroker kits that are available for the H22, there's some options available, but only a few of which are at all realistic. Supposedly JUN makes one, but I wouldn't know where to start to find it for sale. And knowing JUN, it's no doubt obscenely expensive. Another option I'm semi-aware of is via Top Fuel. The page is all in Japanese, but it appears to be a kit w/ crank, rods, & pistons, costing 168k yen (~$1,500). This seems to be too affordable to be true, though - and again, I wouldn't begin to know where to purchase it.

Or you could go the Crower route - custom Crower crankshafts start at about $2,600. Pair it up with custom rods & whatever pistons you like, and there's your kit. The last possibility that I know of would be R&D Dyno - they advertise 2.4 liter shortblocks assembled starting at $4,500 - or unassembled kits starting at 3 grand.

Assembly:
For putting your bulletproof bottom end together, unless you've got an incredibly comprehensive home garage, you'll want to have it done by someplace familiar with Honda/import engine assembly with access to a machine shop. Checking clearances during assembly requires some pretty expensive measurement tools, most of which aren't likely to be kicking around an average toolbox. And of course, there's a good chance you'll need machine work done of some kind - at the very least, a fresh hone on the cylinder walls, and often a fresh deck is necessary.

If you're getting a full resleeve, often places like Golden Eagle offer short-block assembly services while it's in their possesion - this is an excellent option in my mind. Simply ship your internals along with the block, and after they get the new sleeves in, they put it all together for a reasonable cost. Then once you get the block back, it's ready to rock - no fuss. The peace of mind (and usually some sort of assembly guarantee) of having this done is a very nice luxury.

[curtis265]

anyway, hope that answers any questions you may have

[Jccck]

anyway, hope that answers any questions you may have

Holy shit Curtis! +Rep for effort.

Well, he did ask the question.. And if he can't find an answer in that novel, he doesn't belong around a car!

[infurNOS]

HI peoples just wanted to know if anyone had any ideas on what some simple additions i can make to my H series engine but still keeping it N/A

Cheers

What are you looking for most (speed/handling/driveability)? Budget?

I always suggest a lightweight flywheel and a HD clutch before any mod, if you want to feel a difference straight away.

epic posts curtis...