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cheebye
08-02-2004, 06:22 PM
Hi,

anyone using an apex V-AFC? Do they really make a difference to the performance of the car for what it's worth?

Retail for those are about $750. I can get it brand new for $400 direct from Japan but if they're just some fancy piece of machinery that just looks good at nite, I'd rather spend the money on a good set of spoon headers first.

Any comments, feedback regarding that v-afc is appreciated!

- M

BLKCRX
08-02-2004, 06:26 PM
You hit the nail right on the ball… there nothing more than fancy blue flashing lights that look ricy at nite time, spend money on a fully tuneable ECU or intake / exhaust mods, or drop in some nice toda cams !! or toda cam gears. Honestly thow the stock exhaust system is good !! as long as you can tune your car for it…..

Check out the ECU compression thread

http://www.ozhonda.com/forums/viewtopic.php?t=2915&start=0.

Regards James

XXpl0Sive
08-02-2004, 06:27 PM
Sorry to hijack, anyone use the SAFC as well? What are you thoughts on this?

BLKCRX
08-02-2004, 06:29 PM
SAFC VAFC same stuff... VAFC just has a basic vtec on / off feature....
Most .. well ALL vtec controls only turn vtec ON / OFF at a certain RPM, Honda designed VTEC to be turned on with oil pressure is correct, manifold pressure is correct... engine load is correct and rpm is correct.... it shouldn’t be turned on / off !! not only you need to provide the correct ignition and fuel for the cross over period, no vtec controller does this, and not many after market ecu’s do this either !!

Regards James

Setanta
08-02-2004, 07:13 PM
It's a waste of money as James said. Keep saving on the money you would have spent and eventually get a fully programmable ECU.

MRJDM
08-02-2004, 07:26 PM
dude its all so fancy as james said.all im saying is listen to james he knows his stuff
im going to get the HONDATA chip very soon and i know it will be worth it
8)

A'PEXi
09-02-2004, 06:42 PM
its not totally a waste of money if all you want is to make vtec/air/fuel adjustments. its made for a reason.... of course, ecu's open up your options, but its also more expensive.

vti-2
09-02-2004, 07:02 PM
its not totally a waste of money if all you want is to make vtec/air/fuel adjustments. its made for a reason.... of course, ecu's open up your options, but its also more expensive.

I agree that it's not totally a waste of money. If you have lots of mods already, then forget the VAFC, save for a proper aftermarket tunable ECU. If you just have I/H/E and are looking at adjusting vtec/air/fuel (as said above) then go for it. It's fairly cheap and will do the above.

BUT, do not get this just because it can adjust the VTEC crossover point. So many guys buy VAFC's purely to bring VTEC in earlier. It does NOT deliver more power and IMO only makes a shitload more noise earlier in the RPM range. In fact, there are a few guys in Melbourne that have had their cars dyno'ed with VAFC adjustments (set to 4000rpm etc) and have lost power. Coolies on this forum had a piggyback unit (yes it wasn't a VAFC) but it had VTEC set lower than the standard VTEC point and he was being robbed of power. Just ask him and pornstar!

Bottomline what everyone is saying, don't get this for the rice factor. There are better ways to spend money on making the car go faster! :D

VTEC16
09-02-2004, 07:16 PM
What do the "fully tunable ECU" preachers say to the above statement?

Do you guys think that if your only doing limited mods (i/h/e) then the VAFC or fields vtec controller would be worthwhile (keeping in mind the cost)?

Obviously the piggyback ECUs dont allow the same gains....but is it still worthwhile?

BLKCRX
10-02-2004, 07:45 AM
VAFC's do bend the ouput voltage of the ECU, which imminently after the tune is great, although the changeable points is very very limited, and only adjusts full throttle, but the ecu will learn and over write all the VAFC fuel settings due to the long term and even short term fuel trims.
Which results in the car's with VAFC's requiring another dyno sessions, there's only so much piggy back devices can do.

I find a lot of people spend a little bit of money on pointless modifications, rather than saving a little and getting the best....the amount of untuned vafc's running around out there is crazy ! purely because of the fact the ecu will auto learn.

A typical stainless steel exhaust system with a nice mulfer costs around 1500$ + add on the cost of extractors and that’s upwards $3000. Now I can guarantee you will get more HP increase from tuning a stock car with a fully tuneable ECU than you will from bolt on modifications such as a new exhaust with extractors for much less than the cost of a ECU, iv done the tests and proved this many times the stock exhaust is not “THAT” bad anything can be improved upon tuning is where all the power is.

Regards James

Weq
10-02-2004, 12:03 PM
lol, if u pay $3000 or a full stainless exhaust system, ur a crazy man!

BLKCRX
10-02-2004, 02:25 PM
eheheh 800$ apexi mulfer
1500 jap or us exhaust manifold ( extractors)
leaves like only 700 for labor a cat the rest of the exhaust.... mandrel bends.. etc ;-)

anyway back on topic...

Regards James

pornstar
10-02-2004, 03:27 PM
hahaha, yep Coolies got owned definately.

Well I think a piggy back like a VAFC, SAFC etc are partly show and aprtly go. Yes u do get some gains from them in power, noit as much as a full tuneable ecu, but then again compare the prices of the 2 things. one ranges from 750 installed and tuned, another 2,000 installed and tuned.

Switching VTEC in earlier than 5,500 rpms will result in a power loss. No matter what air fuel ratio ur going to run, what ignition, etc, early VTEC engagement is not beneficial simply cos the Second Cam profile wont make anymore power below this, in fact the overlap that the aggressive cam provides will make u lose power.

Coolies ran a greddy that was poorly tuned, not only did he get poor fuel economy, he was actually slower than my stock car.

In summary, the piggy backs are an option fi u dont intend to modify the car much. they do make gains, but vtec swithcing alone wont.

Geek
13-02-2004, 01:29 PM
cr@p.. I didnt know you actually lose power from vtec contollers.. if that were the case y would they have invented them?

also I was going to get the vtec controller add-on for my unichip the geeks that work at the shop that do this stuff reckon it will make a big improvement.. I dont know so what do u all reckon.. Im guessing no from what I have read above :roll:

McChook
13-02-2004, 01:44 PM
delete

VTEC16
13-02-2004, 01:48 PM
The VAFC is able to adjust the VTEC crossover points, as well as the fuel....but i would say that most people (who buy it other than just for the bling) would use it mainly for the fuel.....if you have different cams, then it might be worthwhile tuning in the vtec crossover, but otherwise it appears not...

McChook
13-02-2004, 01:54 PM
you have different cams, then it might be worthwhile tuning in the vtec crossover, but otherwise it appears not...

MOST cams are designed to engage hicam at 5500rpm. I would doubt anything less the specificly designed cams would require moving the changeover point. I know none of the Toda cams from spec A - C need moving, obviously spec D's do - because they are VTEC Killers....

VTEC16
13-02-2004, 04:14 PM
I dont really have experience with changing cams....but i didnt think it was as clear cut as that? depending on one's setup, isnt it possible that a smoother curve would be obtained by tuning the crossover point on more substantiall modded engines? ...or is this just some theory i concocted in my head?

McChook
13-02-2004, 04:15 PM
I dont really have experience with changing cams....but i didnt think it was as clear cut as that? depending on one's setup, isnt it possible that a smoother curve would be obtained by tuning the crossover point on more substantiall modded engines? ...or is this just some theory i concocted in my head?
the latter.. not too sure what you are saying to be honest

VTEC16
13-02-2004, 04:21 PM
....if you moved the crossover point, you obtain a smoother power curve from adjusting the X-over point...and hence gain some midrange?

McChook
13-02-2004, 04:22 PM
....if you moved the crossover point, you obtain a smoother power curve from adjusting the X-over point...and hence gain some midrange?

this would be a cam thing, so it would be cam dependant. I haven't come across a cam that isn't designed to go on hi at 5500, therefore the changeover stays the same

VTEC16
13-02-2004, 04:23 PM
ok fair enuf....thanks for the insight ;)

McChook
13-02-2004, 04:28 PM
ok fair enuf....thanks for the insight ;)

hope that makes sense...
I might be wrong too, need dynodave or an expert to be precise about an explanation....

VTEC16
13-02-2004, 04:55 PM
ok cool...

soul4real
13-02-2004, 06:40 PM
You gain more midrange power, but at what expense ?

DarkCoupe
16-02-2004, 07:42 PM
700 bucks for labour to install some headers and an exhaust?!?!?!? something is wrong there ...