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This moring driving to skool.

i wanted to test mine out. got her up to 8100rpm in seccond and then it cut out completely.

mind you this is with stock everything, except filter, cooler n xhaust.

however my cars been messed with, ive had it up to 220+kmph.

however i drive my other mates car (r33) and i had got confussed because i didnt know why the power cut out at 7ish, wel now i know!

cheers

You havent lived till youve heard a '25 @ 9000+ RPM :)

Id love to hear that @ 7000rpm the engine doesnt sound stressed at all it feels like it could rev to 9000rpm without a problem although im sure it wouldnt last long if you did. The RB25 is Such a smooth engine especially when your previous car was a V6 VN commodore.

Id love to hear that @ 7000rpm the engine doesnt sound stressed at all it feels like it could rev to 9000rpm without a problem although im sure it wouldnt last long if you did. The RB25 is Such a smooth engine especially when your previous car was a V6 VN commodore.

Yeah the sound on the RB25 is unbelievable!! Sounds great at 7,000rpm's with a screamer pipe and no cat.. lol

I could not believe how smooth it is for a 2.5ltr. Very smooth when your previous car was a 60kw 1.6ltr nissan exa.. lol

Greg

also saying that if u shif up you will end up going faster isnt as ture as it sounds. the fact of the matter if u shift at the limiter would will be futher along in the next gear.

not correct, if you shift @ the end of the power band rather than keep going another... 500-800rpm then the car will be faster.

changing from 2-3rd say, you aint going to loose 4000rpm.

The car shifting @ the end of thier power band will be faster.

EG. Car stops making power @ 6500rpm, and you rev to 7000rpm where the last 500 is a struggle for the car and the turbo and 6500 shifted car will be faster.

look in the drag section on the forums. Been covered before

yeah blocked da plum back tube....n tried adjustin da bov as well....at 3000 to 4000 rev if i shift from 1st 2 2nd....da rev jus drops below 1000rev and engine cuts of....it seems like fuel is cut out....i wuz wonderin whether its cus da hks bov is exactly where the stock bov used ta be...

Put the stock on back on. Problem solved

Its a common problem. Look in the sticky @ the top of this section.

It contains the answers if you dont wanna search

My r33 s1 rb25det, has a rev limiter of 7100rpm. secondly i dont see how if tacho read 7000/7100 is only reving to 6700-6800  :angry:  :)

also saying that if u shif up you will end up going faster isnt as ture as it sounds. the fact of the matter if u shift at the limiter would will be futher along in the next gear. i have drag many mid mod r33, (exhuast,fmic,airfilter the normal) and i have a Rb20 turbo on my car making farless as quick as a normal r33 would be with my mods and i can beat, keep up with them due to them shortshifting and me pushing all the way to the limiter (when i say shortshifting i mean they shift around 5500,6000rpm)

just my 2cents

What r31nismoid said, if you shift at the end of your powerband(which i cant ell u wont be the redline if u have the stock turbo) u will be faster. also im assuming all your races have been on the street, and therefore mean nothing, go to the dragstrip and try it out, i have ;)

Also i should have explained about the revving thing. the tacho is not correct. true engine revs can be seen on the powerfc handcontroller, if you have one, and this is what i am talking about.

the faster the car is revving up the more incorrect it seems, ie in lower gears the tacho does not keep up with the revs up the top, which is why when is shows 7000 it is in reality lower, which is why u can rev it into the red zone and it looks like u are revving at like 7300 or something.

on my 33 it came from japan without a rev limiter....i discovered this after buying it and driving off down the road, took a corner sideways and looked at the tacho and saying 'shit it's at 8!'

I used to take it to 8k rpm quite frequently, and on flat shifts sometimes it would tap 9k rpm for a split second.

With all this in mind i wouldnt' recommend taking stock rb25det over 7k rpm! its not a rotor!!!

My d spec pfc came out of the box set to 6900rpm.... So i left it alone....

Once the gt30 goes on i will lift it to 7500rpm... but my motor has only done 4000kms so im going easy to start with....

Edited by Col-GTSX
on my 33 it came from japan without a rev limiter....i discovered this after buying it and driving off down the road, took a corner sideways and looked at the tacho and saying 'shit it's at 8!'

I used to take it to 8k rpm quite frequently, and on flat shifts sometimes it would tap 9k rpm for a split second.

With all this in mind i wouldnt' recommend taking stock rb25det over 7k rpm! its not a rotor!!!

but that only means the ECU wasnt stock

I would have thought that if you look at a dyno graph that shows torque curve, and found the spot where the peak torque hits, then you would want to be at that rev in the next gear you select.

so lets say redline is 7K.

dyno shows that max torque is at 4500rpm.

and lets say you the revs drop 1500rpm between 2nd and 3rd gear.

in this (obviously incorrect) example, you would want to change from 2nd to 3rd at 6000rpm.

does that make sense to anyone else?

The default Power FC rev limit for an RB25DET is 7,500 rpm, that's real RPM as measured by the ECU.  Not necessarily the RPM displayed on the tacho.

:) cheers :)

My power fcs factory setting is 6900???

At what rev range do the hydrolic lifters start pumping up though? this would be the main issue regarding revving high before the rods etc start bending.

ive got a set of GTR rods at home , thinking about whether solid lifters are required to have the 25 revving to 8000rpm as limit with the bigger 3040 turbo and cams!

  • 1 month later...

can someone confirm if the rev limiter on RB25's is a fuel cut or ign cut???

Ive just sent my ecu away to have a few things modified on it and asked for it to be changed to an ign cut!

i want it to be able to sit on the limiter not just die in the arse (not sure which one does which), please let me know so i can call up and cancel it if necessary!!!

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