Is 8,000 RPM on a stock H22 safe? I've got a reprogrammed ECU and I'm still not hitting the limiter at an indicated 8K RPM on my Accord tach.

 

Well 7700 is the stock fuel cut for the h22 but I'm not sure how you're actually going to find out what rpm your engine is really at (unless you have a V-AFC or something). If the Accord tach is anything like the prelude tach then it will read about 8200 when you hit fuel cut. What is your ECu programmed for?

As for your question, I would say no. 8k is probably not that safe with the stock valvetrain and bottom end.

Gabe


[Modified by Gabe, 3:08 PM 8/13/2001]

 

Thanks for the reply man. This is pretty confusing. I got a P13 ECU from a dude that said it had been moderately reprogrammed (different EPROM) fuel and spark curves and 9K limiter. He also shipped the stock chip(s?) with the ECU. When the shop put it in the car, I told them to use the stock chip/s first so I can get a good baseline dyno before I start tweaking/modding. Anyways, the shop said they put the stock chip into the ECU and gave me two funky looking aftermarket chips that were in the ECU, so I'm pretty sure I've got a stock ECU program right now and my tach is as inaccurate as the Lude tach. I can't be sure though.
So anyways my car rips to 8K RPM and I hope I'm not hurting my engine. I've got a VAFC going in in a week or two. I'll try to take it easy on the revs, but ya know how addictive those high revs are...

 

Yeah that sounds pretty confusing. Hope you get it all sorted out.

Yes I sure do.

Gabe

 

..Gabe, 8K rpm on a stock h22 valvetrain, rod ratio, etc., is definatly not healthy!
A friend of mine was using an obd 1 p72 reprogrammed to h22 specs w/ 9k rpm redline in his h22 hybrid Accord, and mis-shifted on the track and ended up bending a number of valves!
However, if your using Ferrea roller rocker, 5000 rpm to 12,000 rpm powerband, valvetrain and have had the motor de-stroked to 2.0 ala Toda/Mugen Formula 3 MF 204B h22, then 8,000 rpm is nothing. I forger who, but there is someone competing in the Speedvison cup using this valvetrain on his h22, and the car sounds insane, WILL NOT idle below 5000 rpm!
Here it is:


[Modified by bb6h22a, 12:57 AM 8/14/2001]


[Modified by bb6h22a, 12:59 AM 8/14/2001]

 

I am running the spoon P13 program on my H22a powered 1993 Accord. Runs great and no problems at all up to this date. I spoke to Joe Sawyer at Hasport and he said that 8500 rpm is safe for the H22a.

Mark

 

Well believe him if you want but when your valves get bent, your rod bolts begin to stretch and your rod ends become elongated don't come crying to us. Go to him and tell him that he said it would work. I bet he won't give you money for a new valvetrain and bottom end.

8000 is probably pushing it on a stock head and bottom end.

Gabe


[Modified by Gabe, 8:26 PM 8/13/2001]

 

Hmmm. Seriously, this would be a good question to ask a Spoon Sports tech to see what they have to say about it.

Mark

 

Well with your JDM motor and Type S internals, you're probably safe in the lower 8K range.
Does anyone know at what RPM valve float occurs in USDM H22s?

Man the thing revs so goddamn fast it's hard to shift before 8K.

 

[QUOTE]Well believe him if you want but when your valves get bent, your rod bolts begin to stretch and your rod ends become elongated don't come crying to us.
QUOTE]

but wait, if the stock rev limiter hits at 7.7K, the what is a 300 rpm differential? Come on, Honda built a window of safety into that ECU. Your friend hosed his motor because of a misshift. Going from 5th to 2nd. somewhere around 10K-12K or higher rpm for a second on the motor, and the valve float. The pistons then bang into the valve, they bend, game over.

 

i might disagree with asking spoon sports about the h22. they dont **** with the h22 at all; never made anything for it, never designed stuff, nuthin.

 

I said 8K was probably the upper limit for what it can do on stock internals. We could do this all day.

you: Well why can't i rev to 8K, it's only 300 more rpm's?
me: Go for it, it's your engine.
you: Well then I should be able to get to 8.3K since it's only 600 more rpm's.
me: Go for it, it's your engine.
you: Aw $hit, I bent all my valves.
me: It's your engine.

while 300 rpm's doesn't sound like much it's more piston and valve speed and when fractions of a second count, higher speed is not usually the answer. I am sure that the honda engineers designed the engine to operate a little over the fuel cut but sometimes 300 rpm makes all the difference in the world.

Gabe

 

I agree completely. I don't think that Spoon or Mugen could tell you much about the operating characteristics of the H22. They sure could school you on B series engines though.

Gabe

 

Is it possible to get an optimal rod to stroke ratio with the H22 without decreasing its displacement?

 

Deck the block and get custom rods.

 

talking more about F3 toda/mugen engine..

mugen knows a lot about H22a..they've worked alot with that enigne for F3 cars and other racing cars that uses/ or used H22a as a base

though as most real racing engine..they really don't idle well for street
but that's mostly due to the cams beeing wide open on all the lobes..


i don't see why the h22a with a destroked kit and a good B/S ratio with upgraded valvetrain and custom grind cams wouldn't rev past 8K ..
i would say it is very fesable to go at 10K with this engine as base...if u follow the same concetp as toda/mugen..

the only thing would be to maintain very consrevative low profile lobes on the cam..and not go to agressive on the vtec lobes..

after all..the H22a is still based on the same technology and base design than the B serie engine ..

i would defenitly get the complete engine overhaul and balanced though ..to perfection for +9k with it..

eheh
i'm sure it would put some real power at 9KRPM
ahah


how far spoon went with the B serie engines ?
12K RPM ? isn't it ?

 

My mechanic insists anything above 8,300 RPMs is murder on the Prelude tranny. He says the tranny just won't let you shift above 8.3K RPMs; like the synchros don't line up or something.
What'd y'all think? Is he full of it?

 

You have a point regarding not using the VTEC lobes on high revving h22's!
The race car using the Ferrea roller rocker setup, has no VTEC lobes what so ever!


[Modified by bb6h22a, 11:13 PM 8/14/2001]

 

as for the tranny, please keep in mind that papadakis runs his times with a COMPLETELY stock tranny. so i am absolutely certain 8300 rpm is okay.

 

i don't think stock cams will make power that high, which would make the whole idea pointless.

 

that's why u have to get cam expecifically for ur application

high reving requires less aggressive inputs..or u'll break everything..
u can't trhow in a JUN type 3 and think that u'll pass 9Krpm
ehe
unless u got everything balanced properly and fortified everything everywhere
eheh
( are the JUN cams out here yet ? )

 

well. . . . no, they're not going up in hp, obviously. but they were makin some for me. http://www.h22a.org/jdmh22accord.htm

and here's one that would have been! http://www.h22a.org/vortechcivic.htm

 

I plan on a fuel cut somewhere between 8k and 8.5k, depending on what the dyno's look like... H22 rods are strong, they can handle that kind of stress, however, I have upgraded my springs and added titanium retainers to combat any valve float problems. I also knife edged my crank and balanced my entire bottom end including my crank, flywheel, and clutch plate, and blueprinted all of the bearings ect...

throw in type-s cams, overbored type-s pistons, and a milled head, and I believe I'll be making safe power far beyond the stock 7600 rev limiter.

But would I do it on a stock H22? Hell no...