I'm debating adding some extra power to my car for some more top end, but if the factory 4 spd auto limits my speed to 120, is there any point? Even if I took the limiter off, I would only have a grand or so left before I redline, which I don't think would add to much more top speed.

Converting the car to a manual or buying a better auto is basically out of the question, so what would you guys recommend to get some more top end?

The car is a '91 Trans-Am with a 305 and auto tranny.

You could add more power and get taller gear in the rear end. (lower numerically) Besides, more power will make you quicker, regardless of your top speed, which, let's face it, you'll rarely get to.

I realize more power will give me better acceleration, which is awesome, but I'm really looking for top end. The car gets to the limiter fast enough, but 120 is weak. I get raped by Honda Accords on the interstate. It's pathetic.

Then have your computer programmed to remove the rev limiter. If that's not enough, then change the rear gears, what do you have in there right now?

Make your point before 80, less chance of getting arrested. Get so far ahead of them in the beginning that they can't see you and there's no point in going any faster.

I'd bet your car probably has 2.73's, meaning that's the best high speed ratio available. The only way to remove the limiter is in the chip.

Why do you think it is the tranny that is limiting the top end? If it is because it won't stay in OD (4th) at WOT that is an easy fix. There is a current thread on how to change this.

If it is because the engine stops pulling at 120 it is the speed limiter in the ECM. Easy enough to program out.

RBob.

Your car will go over 120 ( unless it has had a gear change ) , it has to be the trans not letting you go wide open throttle in overdrive. Like RBob said that is a easy fix so the trans will lock in OD.

Anyone have a link to fix that OD problem handy? Cause I know it jumps down to third at like 100 to pull harder. And as I was saying, the RPMs are running at like 3 to 4 grand at 120 I believe, so removing the limiter would only give me a bit extra top end before I redline in 4th gear.

I always thought it was the speed limiter holding it back though, because it hits 120 and starts to cut in and out I believe. That what it sounds like, and the car shakes abruptly.

I'm running whatever gears came stock. The car has no mods aside from 4th gen front seats.

Dunno if the wire colors would change for TPI, but it's simple & free to "fix"......

https://www.thirdgen.org/unlimited

Here is the thread for the 3-4 WOT shift:

https://www.thirdgen.org/forums/tran...ml#post4057679

RBob.

1000-1500 more rpms in 4th gear would get you into the 150's if im not mistaken, its your limiter. but read up on the kick down threaad

Thanks guys. Good wealth of knowledge here. Try to squeeze that top end out as cheap as possible so all ym funds can go to chassis stiffening, cause high speed wobble can get scary as ****.

Keep in mind, you'll need a fair bit of jam to get to 150 miles an hour.

Not to mention i wouldn't consider going that fast unless you have the right speed rated tires and a somewhat upgrade suspension. i wouldn't get caught going that fast either, that would be a mess

Mess when the cops catch him, or when the T rated tire explodes and you silly string it into the big oak tree on the corner of here and gone? :P

Gonna be a mess when he get's arrestted, or crashes, hopefully not into another car.
Personally I wouldn't tell you how to do it. Going that fast on any public street is just stupid. However if you were doing it to race it that would be different.

I am planning on doing some amateur class racing when i get a racing license. like i said, im not messing with it until I invest some money into my suspension and chassis and obviously my tires. I only have like 50% left on my current ones and they're crap tires anyways.