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Rb 25det Rev Limiter

Branelly

By Branelly,
in Engines & Forced Induction

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R31Nismoid Grand Master

R31Nismoid

Posted
Posted
8500 that would just be awesome, goodbye ceramic wheels thou lol

At 7900 it still does sound smooth =)

:)

Motor RPM is not really relevant to the life of the ceramic wheel.

What kills the ceramic wheel is a combination of heat & RPM, these are directly related to the tune and boost pressure used.

Not a hell of a lot to do with RPM unfortunately, nice try though.

so will the rb25 head macthed with a bigger turbo able to flow good enough to still make power around 7400-7900??? i have heard good things about the rb20 making its way up to 8 or so but the 25???

The RB25 is not a RB20 - They are not the same motor so what one will happily do, has little to no bearing on what another will do.

For long term life of your motor, you apply sane RPM to the motor with stock rod bolts.

Sane RPM being 7000rpm.

IF you do not care how long your motor lasts, then spin it to 8500rpm for a while and enjoy the rebuild process.

Just pray that the rod(s) doesn't go outside the block... it does get a bit messy when that happens.

Granthem Mentor

Granthem

Posted
Posted (edited)

My GT-RS R33 is still limited to factory limiter. 6900-7000, around there. Power is still climbing at these revs, but its not worth the stress a few hundred RPM place on the engine.

I would love to raise it abit and squeeze a tiny bit more MPH in each gear, but I think the life of the standard rods are more important.

Edited by Granthem
Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

I have my rev-limiter set at 7300rpm and pull 3 degrees of timing after 6800rpm so the car is sluggish, this way I never hit the rev limiter, except in 1st gear. What breaks things is actually rev bashing, which I still do LOL

PM-R33 Grand Master

PM-R33

Posted
Posted (edited)

Most aftermarket ECU's have a soft cut limiter and than a hard cut limiter to soften the blow a bit.

I have mine set to 7000 for soft and then 7300 for hard cut i think. I normally shift at 7000 or just before.

Used to have it set to 8000 after the head got built to give it a go, but didn't see the point due to the turbo not making more power that high up in my application.

Edited by PM-R33
Papu Apprentice

Papu

Posted
Posted

My rev limiter is set to 7100 rpm with the power fc, and it feels like the engine is screaming for more revs with a gt 3582, etm manifold, plazmaman plenum etc. Even the tuner asked if he could set the limiter higher because the turbo still kicks in hard. I'm just afraid that the standard internals wont last, and when will the hydraulic lifters stop working so the rev limit is really an issue for me too. How would the engine last with rev limit set to 7500? Or should you change a better balancer first?

Granthem Mentor

Granthem

Posted
Posted
Your GTRS makes power past 7000rpm? Mine doesn't :(

You got a dyno graph?

EDIT: Don't worry just found your dyno graph :)

Yeh i just checked, i guess its fairly slowing down by 7000 isnt it haha.

Hadnt looked at it for a while

JonnoHR31 Grand Master

JonnoHR31

Posted
Posted

relative stress on a motor is roughly equal to power*rpm^2. so if you double the power you double the stress, but double the rpm and you quadruple the stress. hence why revving to 8k for the sake of it is stupid. 8000 puts 1.3 times more stress on the motor than 7000 at the same power level, thats the same as going from 300rwkw to 390rwkw at the same rpm. still sound good on stock internals?

Guilt-Toy Grand Master

Guilt-Toy

Posted
Posted

Every comment in this post has something wrong with it... I would trust a monkey with a bomb before this guy.

8500 that would just be awesome, goodbye ceramic wheels thou lol

At 7900 it still does sound smooth =)

I dont get the Einstein licking a window lol

Oh and their is nothing wrong with Walbro.

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