# GTR R32 Rev limit?



## Ima Racing (Nov 14, 2003)

It will quite happily rev to 9k but was told NOT to even though thats the factory setting. 

What is the safe limit then...will my OMEX rev limiter and launch control work on this car??????..(Sorry for sounding dumb but from Cosworth to a Skyline its a hole new ball game!)


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## dangerous dave (Dec 16, 2003)

on a stock bottom end 7000/ 7500 rpm.
Other wise it can result in oil starvation to the main and most likely big end bearings , they normally spin the bearings in the conrod. Better safe than sorry.


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## davewilkins (Jun 30, 2001)

I thought that the std rev limited was 8250?
I have mine set to 7900 and hit it quite often even in 1st


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## Peter (Jun 27, 2001)

Mine was always set at 7600 rpm, I may up it a bit now but certainly not over 8k....


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## SteveN (Aug 6, 2002)

With the Mines VXROM the rev limiter was set to 9000 on an otherwise std engine.

Its pointless revving over your peak power anyhow, and your peak is going to be somewhere between 6500 and 7500 on a pretty standard car.

All the parts can handle 9000rpm easy, std internals are fookin superb, jus the std oil system isnt up to it really!


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## kingsley (Aug 26, 2002)

It's not pointless revving over your peak power - the ideal time to change would be when the power in the gear you're in now has dropped to what it will be at the revs you'll be at when you change into the next gear (assuming a 'normal' shaped power curve with no funny troughs or anything). That way you'll maximise the area under the graph.


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## DCD (Jun 28, 2001)

SteveN said:


> *With the Mines VXROM the rev limiter was set to 9000 on an otherwise std engine.
> *


Not mine


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## SteveC (Jul 2, 2001)

9000 rpm on the dial is probably about 8200 on the engine as the rev counter is not too accurate.

personally I wouldn't take it over 7500 unless you absolutely have to. or unless you like doing bottom end rebuilds.

/Steve


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## SteveN (Aug 6, 2002)

Ok, let me rephrase it-

Its pointless revving over peak power if your power drops noticably after peak, like it does with engines with relativley small turbos, turbos where they are the main factor over peak power (ie most UK tuned ones, as we generally dont use massive turbos, jus smaller ones to their limit, or well over it!)


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## DCD (Jun 28, 2001)

SteveC said:


> *9000 rpm on the dial is probably about 8200 on the engine as the rev counter is not too accurate.
> 
> personally I wouldn't take it over 7500 unless you absolutely have to. or unless you like doing bottom end rebuilds.
> 
> /Steve *


so you actually mean 6700rpm?? what the hell?


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## SteveC (Jul 2, 2001)

oh Dino... what can you do eh ? 

7500 real revs, according to a real rev counter like an AVC-R or proper tacho.

/Steve


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## Peter (Jun 27, 2001)

The tacho generally isn't that far out Steve, 150 rpm at most....


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## SteveC (Jul 2, 2001)

Mine was about 3-400 rpm out according to the AVC-R. especially at the top end.

Bottom line is 9000 rpm real or not will completely shag the bottom end of the engine in a fairly short space of time.



/Steve


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## DCD (Jun 28, 2001)

Peter said:


> *The tacho generally isn't that far out Steve, 150 rpm at most.... *


...though so


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## DCD (Jun 28, 2001)

SteveC said:


> *Mine was about 3-400 rpm out according to the AVC-R. especially at the top end.
> 
> 
> 
> /Steve *


Maybe the AVC-R is the innacurate one? I mean its not like it reads rpm from its own high-precision rpm sensor...the source is always the same


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## Peter (Jun 27, 2001)

SteveC said:


> *Bottom line is 9000 rpm real or not will completely shag the bottom end of the engine in a fairly short space of time.*


* Absolutely. 

I intend setting mine at around 7750 whenever I get the chance to see those sort of revs again....*


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## kgleeson (Sep 16, 2003)

*Rev limiter*

Hi All,

The MINES VX Rom I had was also set for around 9000rpm.

I was also under the impression that it is not just an oil issue with over revving the RB26 BUT you stand the chance of stretching the standard conrod bolts and then ultimately spinning shells. I am a little concerned that with all my recent mods I can quite happily REV through to 8000rpm and haven't completely lost power.

I have the catch tank, oil cooler etc. to try and ensure the oil flow is reasonable and temperature is kept down. What other MODS can you do to try and keep the bottom end intact? I have been looking at a sump extension kit but not sure exactly what that does! I was also hoping to set a rev limiter on my R33, can this be done through the Power FC? or do you have to buy a "Bolt ON" Rev Limiter.

Lastly !!!!!!!!!!!!!!
Does the stretching Conrod bolts theory standup? If it does then all the additional mods won't really help. The steel Conrod bolts are not expensive at around £120 but I have also been told you really need the engine out to change them and torque them down properly.

As usual more questions than answers.

Kev


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## SteveC (Jul 2, 2001)

then why was it different from the swing needle type rev ounter.

on a dyno the readout is accurate and it always appears higher on the rev counter than on the printout.

why does the revlimiter cut power at a rev display of higher than 8200 rpm ?

the ECU knows how fast the crank is turning and the readout is always different.

the same applies to the consono tool when that is plugged in.
And that used to tie up with the boost controllers readout.

once you are into real revs (not tickover) the rev counter was not very accurate.) this is just my experience and I have done everything I have said.

I can say no more on this subject  

/Steve


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## Emre (Nov 26, 2001)

The biggest downfall of the R32s is the shorter crank collar that drives the oil pump. The redline on the tacho is set at 7500 rpm, so if you wanna rev past that, consider the fact that you may have issues with the oil pump. Having a catch tank will not address the problem, nor having an oil cooler, although it would aid in keeping the oil healthy.

It would also greatly depend on what you intend to do with your car. My R33 has the rev-limit set at 8500 rpm, but i hardly get near it on the street. On the drag strip i always rev right through, but if i was to get on a circuit i would definitely reduce the rev-limit to below 8k rpm.


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## kingsley (Aug 26, 2002)

SteveN said:


> Ok, let me rephrase it-
> 
> Its pointless revving over peak power if your power drops noticably after peak, like it does with engines with relativley small turbos, turbos where they are the main factor over peak power (ie most UK tuned ones, as we generally dont use massive turbos, jus smaller ones to their limit, or well over it!)


It might be pointless going, say, 1500rpm over your peak under these conditions but it is still worth going past it at least some way.

I've got small turbos on my 33 (stock R34 ones). Peak power is [email protected] at 7000rpm or near as dammit (power graph at the bottom of this page - the red line is current spec). If you look at the power graph I think you'll agree the power does, as you describe, drop off noticeably after peak.

If I change out of 3rd at 7000rpm into 4th then I'm dropping to about 5375rpm in 4th, where my engine is making about 325bhp @ hubs.

If I stay in 4th until 7500rpm (where power has dropped to about 380 @ hubs) then I'm still doing approx 5750 in 4th where my engine is making over 340 @ hubs.

Off the top of my head I can't remember how much speed 500rpm in 3rd represents but it's probably about 7mph. So, over that 7mph band, leaving it in 3rd that extra 500rpm means that I'm delivering beteen 380 and 400bhp to the hubs during that time rather than somewhere between 325 and 340bhp.

It doesn't take a degree in rocket science to work out which would give you faster acceleration.


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## Demon Dave (Sep 15, 2002)

*Kingsley*

that makes perfect sense - shifting slightly over the peak power level should keep the engine in the peak power band and thus give you maximum acceleration. Couple of questions:

1. On my standard (ish) R34 peak power is at 6,000rpm so it would follow that there isn't much point in me reving it much pass 6,500?

2. Can anyone post up a dyno graph for a standard GTR for reference?


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## DCD (Jun 28, 2001)

Guys come on. This doesn't make much sense. The reason you shift above peak power is because, depending on gear ratios, you drop rpm in gearchanges so want to drop in a good position in the torque/power power curves, to allow max pick up. 

Obviously none of you have ever driven an RX8


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## kingsley (Aug 26, 2002)

Dino, I believe my post offers a mathematical explanation of what you said, or do you disagree? Never driven or been in an RX anything - what's the deal there?

Dave, you need to get a dyno graph really and compare against gear ratios (you can look up the ratios on this site under the technical section - do you have a GTR?). I think there's an R34 GTR dyno graph on there too. Ideal shift points will vary from gear to gear because higher gears are closer together percentage wise, amongst other reasons. Assuming a nice smooth power curve ie no sudden flatspots) then IMHO maximum acceleration would be achieved when max power in the gear you're leaving matches what it will be in the next gear when the revs drop. That way, you maximise the area under the "driving force over time" graph.


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## BBD (May 30, 2002)

without high duration camshafts and uprated Turbos it is really pointless revving the engine past 7.9k.. RPM doesnt mean power or your car will be faster, you have to know your Powerband and torque curve to know exactly where to shift and how far your rpm drops in gear changes.


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