1999 Pontiac Formula top speed?
 

So I just recently bought a 1999 Pontiac firebird formula with the LS1 and it tops out at 135 I thought at least I could get 150 out of this car it has 90,000 miles on it and a ws6 hood ram air intake and nothing wrong with it at all.

Top speed is 162-163mph with the factory speed limiter in place (lower if the car was not originally ordered with Z-rated tires).

Is there a governor on it I have the z rated tires?

If its an auto it wont shift into 4th under wot right??? 135 would be about max for 3rd with 3.23 gears i think.

Yes it is a auto I'm not sure if it shifts or not I can't concentrate on that at that speed next time Im in Mexico I
will check

?

My car shifts in to 4 under WOT all the time. It holds 3rd gear longer, but it still shifts, it doesn't just bounce off the rev-limiter?

Im going to check now just got off

I've never gone faster than 135MPH because my car starts shaking and I don't trust the 20 year old suspension, but if I'm already in 4th gear and slam the throttle, it downshifts in to 3rd and goes up the power band and shifts back in to 4th. Like 4->3->4. Is it not supposed to? I'm confused, now. lol

From first to second I have to let off the gas when I shift into third it shifts just fine and I can stay in the third until 135 then when I shift to drive it shifts so I know it has more than 135 now but my car started shaking so I'm not ever doing that again until I get new tires and my suspension fixed haha

Referring back to post #4, WOT does not prevent an 'auto-shift' from 3rd to 4th, what WOT prevents is the torque convertor lock-up clutch from engaging.