Stock B20VTEC, danger inTorquing ARP ROD BOLTS and Revving to 8000rpm on stok block

[UN11QU]

Hey Guys just wondering are there any dangers of torqueing arp rod bolts to the stock rods?.
Would they crush the bearing? Or is it pretty straightfoward?
How many people have managed to do this without any issues?

and
How much risk is there revving to 8000rpm on a completely stock bottom end of a B20B8, not even arp rod bolts?

Thanks guys

[Samm928]

why you being a tightarse if your doing b20 ?

just buy the bolts!!!!!

[VTec1987]

do it once and do it right......

[OMG.JAI xD]

I dont think bearing crush is dependant on the bolt you use. The bolt it self only transfers clamping/holding force.

As long as the torque is right, youll have the same bearing crush with any bolt, if its the same pitch, width, depth, length etc.

You should always consult the manual though. Some bolts may have different tolerances and may differ in torque settings.

[Chr1s]

why you being a tightarse if your doing b20 ?

just buy the bolts!!!!!

Why is he being a tight ass? Care to clarify the NEED for ARP rod bolts? What's your experiance with standard rod bolts and installing ARP rod bolts without the correct procedure?

Don't tell me your getting your advice from another forum, please tell me it's educated and/or experimental advice.


I dont think bearing crush is dependant on the bolt you use. The bolt it self only transfers clamping/holding force.

As long as the torque is right, youll have the same bearing crush with any bolt, if its the same pitch, width, depth, length etc.

You should always consult the manual though. Some bolts may have different tolerances and may differ in torque settings.

Good theory but you contradict yourself here. The bolt transfers the clamping and holding force, true. Yet you should know that ARP bolts require more torque, what's this do to the caps? It's stressing them ever so slightly. Ever heard of the term "out of round" on the big ends?

OK lads,

We know from our primitive instinct that a circle is one of the strongest shapes known to us, we try compress a circle shape, and it resists if being supported well, otherwise it will bow out and become an elipse. Lets say you get your ring, the type you wear on your finger, you try squeeze it. What happens? **** nothing. You put it in a vice, what happens? It becomes elongated in the perpendicular direction of the force, in otherwords, an elipse out the sides of no load. If you were to support the ring while in the vice so that it can't move, and apply the force, what happens? It will try buckle, yes? We just proved that the shape failed and bowed out the sides, so why won't the ring deform in another way?

That is exactly what's happening when you install ARP rod bolts into a standard rod, maybe you get lucky and you won't need to close and hone the big ends, sure, plenty of people do it, but plenty of people don't service cars, sit on the limiter all day, don't warm their cars up, yadadyadad. Alot of other people will have another opinion on installing rod bolts too from their experiance, but it's not the right way to do things.

If you want to uprate the rod bolts, pull the rod out, torque it to spec and perform the required machining, if any.

[TODA AU]

If you want to uprate the rod bolts, pull the rod out, torque it to spec and perform the required machining, if any.
This is the correct way to do things. you may or may not need to close & hone the rods.
(The risk of change is low due to the similar torque specs)
But you should always double check your work.
If you don't, you won't know until thing go pear shaped later on which will likley be an expensive mistake.

FWIW, Close & hone of the rods is a basic machining (low cost) process that 99% of machine shops are well versed in.
So if you change the bolts, (it's been said before) do it once & do it right.

[Samm928]

Why is he being a tight ass? Care to clarify the NEED for ARP rod bolts? What's your experiance with standard rod bolts and installing ARP rod bolts without the correct procedure?

Don't tell me your getting your advice from another forum, please tell me it's educated and/or experimental advice.



Good theory but you contradict yourself here. The bolt transfers the clamping and holding force, true. Yet you should know that ARP bolts require more torque, what's this do to the caps? It's stressing them ever so slightly. Ever heard of the term "out of round" on the big ends?

OK lads,

We know from our primitive instinct that a circle is one of the strongest shapes known to us, we try compress a circle shape, and it resists if being supported well, otherwise it will bow out and become an elipse. Lets say you get your ring, the type you wear on your finger, you try squeeze it. What happens? **** nothing. You put it in a vice, what happens? It becomes elongated in the perpendicular direction of the force, in otherwords, an elipse out the sides of no load. If you were to support the ring while in the vice so that it can't move, and apply the force, what happens? It will try buckle, yes? We just proved that the shape failed and bowed out the sides, so why won't the ring deform in another way?

That is exactly what's happening when you install ARP rod bolts into a standard rod, maybe you get lucky and you won't need to close and hone the big ends, sure, plenty of people do it, but plenty of people don't service cars, sit on the limiter all day, don't warm their cars up, yadadyadad. Alot of other people will have another opinion on installing rod bolts too from their experiance, but it's not the right way to do things.

If you want to uprate the rod bolts, pull the rod out, torque it to spec and perform the required machining, if any.


relax yourself puppy.

"do it once, do it right"

[Chr1s]

relax yourself puppy.

"do it once, do it right"

Relax myself? In what way?

I asked you a question, don't be a politician and reply with another general statement or question. People want answers.

Can you explain to me how you stumbled across "do it once, do it right?" - you clearly have experiance in this field, especially when it comes to rod bolt selection and what type to use.

I'm seriously interested. If you don't know, or don't know how to explain it, just say so. Plenty of people on here are curious too. Even the OP.

[Chr1s]

Tried to PM you Sam

[GSi_PSi]

i dont think the engine will last long revving to 8000rpm on the stock D series rod bolts, which many many people have said they are the main weakness of the revability of the stock b20 bottom end.

[Samm928]

he may be revving to 8000. but depends on how constantly he does it.

oneor twice a day ok.

but at times with your usual 8000rpm rev especially with hondas. you want it to go harder than 8000.

i personally was thinking about doing b20 until i found alot of cooling issues with the b20.

[GSi_PSi]

with a proper breather system setup cooling should be fine

like sam said one small overrev like flatshifting , very very dangerous

[Chr1s]

Sam have you had overheating issues with your b20?

I've never seen a b20 yet thats run hot, unless the obvious with lack of water and shit working cooling system lol

[GSi_PSi]

Never had overheating issues, but without a breather setup the car would lose a bit of performance after giving it for a good hour or so

[tinkerbell]

wondering are there any dangers of torqueing arp rod bolts to the stock rods?.
How many people have managed to do this without any issues?


to add my experience to the extensive survey of people who have actually done it.

whilst knowing the risk, I have installed ARP rod bolts in two B20VTECs without checking for warpage of the big-end ID...

and after many hundreds of circuit racing laps, I am happy to say there did not appear to be any detrimental effects…

hence, in relation to installing ARP rod bolts without removing and checking the big-ends, I would suggest that you can probably "get away with it", but that is your own risk.

[GSi_PSi]

but the question is what is worse? and what is more likely to cause engine failure ?
Revving the b20 completly stock to 8000rpm or installing rod bolts in the block

[tinkerbell]

well, in my experience:

1. the bottomends were fine (no rod bearing issues)
2. i didnt throw a rod due to rod bolt stretch/failure

and

3. by not removing my rods & pistons i didnt have to worry about installing new rings and bearings (plus the added costs) and the issues that might be associated with new rings & bearings...

but again - it was a risk to not check the distortion potentially caused by the different rodbolts....

[JS2k]

The last of your worries are the conrod bolts when your revving an engine to 8k, only forced induction applications require ARP rod bolts etc

I can assure you Honda Engineers test these engines to extremes, much better that what you can

[Chr1s]

Funny you say that, naturally aspirated engines put more stress on rod bolts and rods.

Honda engineers also test their engines extensively, but only for what they are designed for. The B20/18 motors wern't designed to see 8000rpm onwards, they may be able to handle it no problem, they may not, nobody here obviously knows enough to put some hard fast facts down and Honda more than likely didn't test for it either. I personally think that standard rod bolts will be fine in stockish cam configurations.

[tinkerbell]

I can assure you Honda Engineers test these engines to extremes, much better that what you can

so Honda tested the B20B's to rev past 8000rpm for extended periods? wow, that is interesting information! what is your source?

[JS2k]

Tinkerbell and Chr1s - can you please show where i mention that Honda has tested these engines at extended periods at over 8000rpm??

What i said is Honda and other manufacturers do test there engines extensively at extremes, additionally manufacturers rev limit is normally a safe guard for the engine not a absolute maximum!!

I hope you didnt think Honda would hope nobody ever revved a B series engine above its limits and just hoped for the best! everything is manufactured with a safety net involved

I dare say, a decent set of conrod bolts is important in a engine rebuild for HP applications, although turbocharged or forced induction methods create more stress on the conrods and bolts than what an NA application would , but then again what would i know i have only been building engines for 15 years

We all have different opinions and ways of building engines, as good practice i would replace the mains and conrod bolts with new OEM items

anyways i wont get into this argument any longer, just my two cents

[GSi_PSi]

I dont think you understand that a B20's stock rev limit is 6500rpm, the engine was not designed to be constantly reach rpms of 8000rpm so they used D series 1.2L to 1.6 Litre rod bolts into the engine as it was the most practical to the cost/benefit analysis, and many people when first building B20's in the states have concluded that the rod bolt was the culprit of many blown engines. I can see the problem is you probably haven't come across or know anything about B20 Frankenstein or what is needed in building them so your probably just generalizing that most non turbo applications are safe without aftermarket rod bolts and you would most likely need them in forced induction applications, were most of the engine internals need to be forged or can withstand much more pressure

[Chr1s]

Well, this is a forum and everybody is open to an opinion, so here's mine.

In a forced induction motor, you have a condition where the engine is always under positive pressure. In a naturally aspirated engine, we often find a vacuum or an atmospheric condition present depending on how efficient the motor is.

So what? Well think of the process the rods and rod bolts see, the changing ingress of stresses is what i'm talking about in particular; Tension and compression.

Compression occurs when the piston is "pushing" down on the rod, this induces stress in the rod near the wrist pin, this kind of stress will lead to a bending type of failure. There is no stress on the rod bolts at this point, if anything, this is where the importance of oil pressure between the bearing and journal is needed to avoid contact. For an increase in BMEP (power) there is the requirement for an increase in oil pressure. But this is another story.

Tension occurs as the piston is "pulling" on the rod and peaks in stress when the crank changes direction, imagine sprinting as fast as you can and then stopping and trying to change direction as fast as you can, the inertia would be huge. As mentioned earlier, a failure at this point would typically yield a rod split in two. What has rod bolts got to do with this stress? Well when the rod is under tensile stress, the bottom half of the rod cap is resisting this force due to the oil pressure again between the bearing and the journal. This resistant force is transmitted to the rod bolts which results in, you guessed it, tensile stress. Now we've realised that this kind of motion isn't present on the compression stroke, hence the term compression, the rod is subject to compressive stress, when the power stroke is occuring, the compressive stress is releived and the rod is in a happy state, so this rules HP out of the equation for stresses implied on rod bolts. Obviously the rod has to have a suitable second moment of inertia to sustain large compressive stresses. Although I will guarantee you that the tensile stress acting on the rod is much greater than the compressive.

It should be common sense now to see how a rod is affected now by the greater pressure differential as it sweeps from TDC on the intake stroke (overlap, MAP, tensile) in a naturally aspirated motor.

Why HP has nothing to do with how strong a rod bolt is? Because the tensile stress present on the rod bolt is what kills them, and the faster you spin the engine, the greater this becomes. THIS is why I say, RPM kills rod bolts.

Generally speaking, higher HP engines require a greater RPM to make this higher HP, this is why items fail in this manner and people just resort to "oh it's because of the power" mentality. Remember your simple Physics.

Oh by the way, you may have been building engines for the past 15 years, which no offense, means jack all to most educated people, although keep in mind you might be talking to an ex F1 engine developer one day.

[tinkerbell]

Tinkerbell and Chr1s - can you please show where i mention that Honda has tested these engines at extended periods at over 8000rpm??

well, right here:


I can assure you Honda Engineers test these engines to extremes

got a dictionary handy?

A S S U R E


–verb (used with object), -sured, -sur·ing.
1.
to declare earnestly to; inform or tell positively; state with confidence to: She assured us that everything would turn out all right.
2.
to cause to know surely; reassure: He assured himself that no one was left on the bus.
3.
to pledge or promise; give surety of; guarantee: He was assured a job in the spring.
4.
to make (a future event) sure; ensure: This contract assures the company's profit this month.
5.
to secure or confirm; render safe or stable: to assure a person's position.
6.
to give confidence to; encourage.

http://dictionary.reference.com/browse/assure

T E S T


–noun
1.
the means by which the presence, quality, or genuineness of anything is determined; a means of trial.
2.
the trial of the quality of something: to put to the test.
3.
a particular process or method for trying or assessing.
4.
a set of questions, problems, or the like, used as a means of evaluating the abilities, aptitudes, skills, or performance of an individual or group; examination.
5.
Psychology . a set of standardized questions, problems, or tasks designed to elicit responses for use in measuring the traits, capacities, or achievements of an individual.
6.
Chemistry .
a.
the process of identifying or detecting the presence of a constituent of a substance, or of determining the nature of a substance, commonly by the addition of a reagent.
b.
the reagent used.
c.
an indication or evidence of the presence of a constituent, or of the nature of a substance, obtained by such means.
7.
an oath or other confirmation of one's loyalty, religious beliefs, etc.

http://dictionary.reference.com/browse/test

E X T R E M E


–adjective
1.
of a character or kind farthest removed from the ordinary or average: extreme measures.
2.
utmost or exceedingly great in degree: extreme joy.
3.
farthest from the center or middle; outermost; endmost: the extreme limits of a town.
4.
farthest, utmost, or very far in any direction: an object at the extreme point of vision.
5.
exceeding the bounds of moderation: extreme fashions.
6.
going to the utmost or very great lengths in action, habit, opinion, etc.: an extreme conservative.
7.
last or final: extreme hopes.
8.
Chiefly Sports . extremely dangerous or difficult: extreme skiing.


http://dictionary.reference.com/browse/extreme


so yeah, whatever, and particularly in the context of a B20/VTEC hybrid engine - maybe you just need to keep in check your use of words? which might be easily misinterpreted?

[JS2k]

well, right here:



got a dictionary handy?

A S S U R E



http://dictionary.reference.com/browse/assure

T E S T



http://dictionary.reference.com/browse/test

E X T R E M E



http://dictionary.reference.com/browse/extreme


so yeah, whatever, and particularly in the context of a B20/VTEC hybrid engine - maybe you just need to keep in check your use of words? which might be easily misinterpreted?

Mate please, were talking engines here

if you want to give english lessons do it elsewhere

After all this is a forum , people can voice there opinions and experiences to help others if possible

We all build engines differently thats will always be the case, if ARP rod bolts will keep you happy and give you the peace of mind you need then have them fitted

Best of luck

[tinkerbell]

Mate please, were talking engines here


so what did the last B20/VTEC you built get used for? drag racing or circuit racing?

[JS2k]

Well, this is a forum and everybody is open to an opinion, so here's mine.

In a forced induction motor, you have a condition where the engine is always under positive pressure. In a naturally aspirated engine, we often find a vacuum or an atmospheric condition present depending on how efficient the motor is.

So what? Well think of the process the rods and rod bolts see, the changing ingress of stresses is what i'm talking about in particular; Tension and compression.

Compression occurs when the piston is "pushing" down on the rod, this induces stress in the rod near the wrist pin, this kind of stress will lead to a bending type of failure. There is no stress on the rod bolts at this point, if anything, this is where the importance of oil pressure between the bearing and journal is needed to avoid contact. For an increase in BMEP (power) there is the requirement for an increase in oil pressure. But this is another story.

Tension occurs as the piston is "pulling" on the rod and peaks in stress when the crank changes direction, imagine sprinting as fast as you can and then stopping and trying to change direction as fast as you can, the inertia would be huge. As mentioned earlier, a failure at this point would typically yield a rod split in two. What has rod bolts got to do with this stress? Well when the rod is under tensile stress, the bottom half of the rod cap is resisting this force due to the oil pressure again between the bearing and the journal. This resistant force is transmitted to the rod bolts which results in, you guessed it, tensile stress. Now we've realised that this kind of motion isn't present on the compression stroke, hence the term compression, the rod is subject to compressive stress, when the power stroke is occuring, the compressive stress is releived and the rod is in a happy state, so this rules HP out of the equation for stresses implied on rod bolts. Obviously the rod has to have a suitable second moment of inertia to sustain large compressive stresses. Although I will guarantee you that the tensile stress acting on the rod is much greater than the compressive.

It should be common sense now to see how a rod is affected now by the greater pressure differential as it sweeps from TDC on the intake stroke (overlap, MAP, tensile) in a naturally aspirated motor.

Why HP has nothing to do with how strong a rod bolt is? Because the tensile stress present on the rod bolt is what kills them, and the faster you spin the engine, the greater this becomes. THIS is why I say, RPM kills rod bolts.

Generally speaking, higher HP engines require a greater RPM to make this higher HP, this is why items fail in this manner and people just resort to "oh it's because of the power" mentality. Remember your simple Physics.

Oh by the way, you may have been building engines for the past 15 years, which no offense, means jack all to most educated people, although keep in mind you might be talking to an ex F1 engine developer one day.

Chris

You make some good points there, let me add some

There is large amounts of torsional forces on the connecting rod , the con rod itself would be safe unless were talking about forced induction

The conrod bolts and cap will have most pressure, although the concern i would have is stretching of the bolts rather than the bolts snapping

Stress fractures can also be a concern, if the engine was not assembled correctly and torque specs and procedures were not followed you could induce a problem early on in the assembly process

As i mentioned earlier we all have different opinions and ways we build our engines, FYI i have used ARP rod bolts, stud kits and gurdle kits before with great success

Well i guess we cant argue with an EX Formula 1 engine developer either, although that also means jack to most people

Best of luck to all, i have added my opinions

Lets move on gents

[TODA AU]

Well, this is a forum and everybody is open to an opinion, so here's mine.


if anything, this is where the importance of oil pressure between the bearing and journal is needed to avoid contact. For an increase in BMEP (power) there is the requirement for an increase in oil pressure. But this is another story.


Oh by the way, you may have been building engines for the past 15 years, which no offense, means jack all to most educated people, although keep in mind you might be talking to an ex F1 engine developer one day.

So do I get you call you an Ex F1 engine developer when you work for a team for 1 week & get fired? LOL…

Also, bearings are filled by oil pressure on the unloaded side…
That is oil is pumped where the load was…
Anyway… I’ll leave it as this could digress so quickly…

[Chr1s]

I don't think i'll be sitting around on ozhonda when if I ever get to f1 LOL

[Cartoon]

chris,

i will still be building my motors tho :)
short stroke v8 honda all the way

[Chr1s]

Jizzle :)