Hey guys quick question for Evo 8's and 9's.

This question is reguarding a *stock* internal and *stock* head/valvetrain Evo 8 or 9 with headstuds.

Is it safe to raise the rev limiter to 8,500rpms?

The Story:
I ask because I know of someone who had raised my friend's gt35r Evo's rev limiter to 8,500rpm with a *stock head w/ headstuds to 8,500rpm and told him it was safe to race and beat on. The very first night out racing the tuner missed a gear while racing and blew a valve. I figur while the car was over-reving it got "valve-float" and bent the valve. They say it had something to do with the anti-lag/no lift shift.... whatever. The car was fixed and the rev-limited was placed at 8,500rpms again. The owner of the car is an unexperienced driver so I asked the tuner if it was infact safe to rev the car out that high; they told me "as long as you don't miss a gear." To me that seems foolish to be driving around a performance vehicle that if you miss a gear the engine could blow? Why even raise the limiter that high? Long story short, the owner took the car out racing with me in it and missed 4th gear and the motor popped: the MAP sensor came off, and a piston was cracked on top from what looked to me like it got interferience/valvefloat when it over-reved. They say it was not because it over-reved and because the MAP sensor came off so it detonated. Others say it's blew because the limiter was too high again but it's "the drivers fault for not being able to shift or understand the tuning of the car."

What are your thoughts on this? *Without* a built head: cams, springs, retainers: is it safe to rev to 8,500rpm and hit rev limiter?

Also, Do any of you guys run your limiters at 8,500 or even 8,000rpm???

Thanks.

 

I think you answered your own question...

 

Your friend should own an Evo if he's that....dumb... I mean really the stock red LINE is at 7000, and they can be taken to I believe somewhere in the 7400rpm range give of take (mine adjusted) before the rev limiter kick's in.

So your "friend" takes it to a so called tuner and they tell him...."f8ck the factory they have no idea what this motor can handle, lets put her up to 8500 rpm on your bone stock valve train"

To answer you question....no, no it's not safe to do.

 

This

 

You are misunderstanding what the rev limiter does - it cuts fuel so the engine will not rev beyond a certain defined point....That said, if you miss a shift and hit 2nd gear instead of 4th, your rev limiter does nothing to stop physics....

So, don't miss shifts....and set the rev limiter to a value you feel is safe based upon your engine...

 

Redline is 7000, rev limiter is 7606. Many flashed brought the car to 7800 for a little bit of headroom. Now they are raised to whatever the owner would like. Many rev to 7800-8000 rpms with no problem, mostly big turbo guys or stock turbos running out 4th gear. It depends on how often you do it and your friend's engine failing had nothing to do with his increased rev limit. It could have been set to 10,000rpms and it still would have happened.

 

at least install spring and retainers but is kind of pointless raise the rev if you are in the stock turbo.

 

I have springs, retainers, cams and head studs; mine is set at 9k. The only time i get close is 4th gear when I am drag racing. Other then that, I shift around 7800 RPM's