WTF is going on?

[fellamansteve]

Before I put my catback and TB on, my car was definitely rev limited to 5800RPMs...I would hit 5800 and the car was definitely not going any higher than that. Now that I have the catback and TB installed, I gunned it pretty good last night and got it up to 6K RPMS for a brief second and it seemed like I could have taken it higher. Should I be concerned?

 

[DBMSTNG]

no, as long as it doesn't go over 6500rpm you should be fine.

 

[GTsleeper]

I agree with DBMSTNG you shouldn't have to worry until u hit 6500rpm's. Also DBMSTNG how do u like those shorty headers I have the same set-up as far as exhaust goes with the x-pipe. Plus how do you like that Vortec set-up. There is an installer right around my house and he charges a grand to install one. If you can hit me back on those shorties I would appreciate it.

 

[nickthegenius]

Before I put my catback and TB on, my car was definitely rev limited to 5800RPMs...I would hit 5800 and the car was definitely not going any higher than that. Now that I have the catback and TB installed, I gunned it pretty good last night and got it up to 6K RPMS for a brief second and it seemed like I could have taken it higher. Should I be concerned?

My tuner told me that all '99-up GTs are rev limited to 6050 and that most factory tachs read low. You can't change the limiter by changing engine parts, its changed by programming in the EEC.

As far as reving the engine, as stated above 6500 seems to be the max with these engines and there have been a few guys at ModularDepot that have lost engines shifting at 6400-6500 at the track.

 

[gtrackd02]

i shift around 5750ish..lol right around there anyway
And for some ungodly reason my revlimiter does'nt kick in until 6750 ish...
My custom tune suddenly doesnt seem too safe anymore...lol

 

[WD-40]

I'm telling you Steve, it's those black tie-wraps. Everyone knows the black ones are the fastest- you even said so yourself.

Either that, or it's the awesome power of my flashlight, which is still in your trunk.

Or it could be that mysterious blue piece we pulled out- maybe that had been holding you back?


Seriously though, maybe the stock TB was just restrictive when it tried to flow the required air at those high RPMS? (ie: maybe you were hitting the physical flow limitations instead of a rev-limiter?)

 

[3.8L_of_Pain]

I had the same experience after I installed the Accufab 70mm TB and plenum. On the first test drive, I bumped the rev limiter which, at the time, was set to the factory value of 6050 rpm.

So the owner of the local performance shop suggested using the Diablo Predator to set the 1st to 2nd shift point at 5900 rpm, and the 2nd to 3rd at 5800 rpm, and the rev limiter to 6300 rpm.