Mr. McGuire

What is the top speed of a STOCK 1991 Camaro with a 305 TPI with an auto trans? I was messing with this VW and the Z28 seemed to peek a 110mph. Thats what my speedometer goes to (110mph). Also whats the best way to increase top speed? I was gonna buy servo and governor kit and shift kit from Summit. Is that the right way to go?

Sean O'Hara

I know the top speed of my GTA with the 350 is about 130 mph

Mr. McGuire

I guess 110mph is about right if thats a 350.

fasteddi

iTrader: (2)

Reburn the ecm chip so there is no limit in the code....Mines at 252 limit, even though it would never even get close to that.

iggy1991

Its governed by the ecm not the trans. The transmission wont even hold 4th gear in wide open throttle.

me420

ive had my z to 130+, white knuckling, windows open, t-tops off, and headliner freshly ripping in the wind. was old anyway and had slight sag. earned a excuse to fix it.

gotta say that upholstery orange stuff hurts your eyes, especialy......rippin'

ghost91

I have the same and fastest ive gotten it before i got scared was roughly 127. even though the speedometer goes to 110, i estimate it at 127. i wouldnt push it much more

me420

yeah once i seen 130 i didnt count anymore but didnt let up either lol

lolvtec

i got rid of my gov with a jet hot chip
91 vert top down i let off cuz of traffic

weeeeeeeeeeeeeeeeeeeee

Chainlynk

I topped out going down interstate 95 at 130 mph 3300 rpm in overdrive in my 86 trans am 305 carbureted 9 bolt rear 2.77 ratio. Speedo goes up to 140. It handled like it was on rails with the 406 I'm building I'm hoping to see the speedo start wrapping around!

DannyJohnson

I think the governor stops it at 115.

utilityguy2

iTrader: (1)

There is no governor. The ECM program has speed and rpm cutoff limiters but they are set at 255 mph and 9544 rpm in stock configuration.

fireburdluvr85

135 with a freshened up lb9. some young punk got tired of being behind my wifes truck when i was a few cars behind and when passing he swerved hard at her..... needless to say the bird caught his camry real fast and some tricks were used to "school" him on driving etiquette. ive got mods to the trans to stay in 4th gear at up to 70% throttle.....

now that i got that outta my system, i didnt know tpi cars had any limiter? i know the tbi cars were 109 or something?

DannyJohnson

Ah, must have only been for TBIs?

Moody13

Ive gotten my 305 tbi to 120 and it still had more...it took a long time to get it there.

RBob

iTrader: (1)

Whether or not there is a speed limiter depends upon the year of the car along with what tires it had from the factory. The TPI cars that were factory equipped with Z rated tires have the speed limiter set high (254/255 MPH).

TPI cars with non-Z rated tires along with others such as the TBI and the 3.1l MPFI cars were limited to around 112/115 MPH. Even this varies to some degree, but they were limited in speed.

The older f-body's that were carb'd didn't have speed limiters.

The limiting is done by setting the injector PW to 0, thereby shutting off the engine.

RBob.

IROZINCO

iTrader: (1)

140mph in my 350TPI 89 GTA on a flat stretch of road (at 5000ft altitude!) And it had more to go, i just ran out of straight road at that point! But the 91 definitely had a speed limiter, though for a stock 305, thats probably pretty close. Its not a hi rpm engine. Maybe 120 max...

TysonNorthcott9

I have a 1988 trans am gta it tops out at 188km/h (117.6 mph) it's a 4 speed auto with o/d and the 350 tpi it's a Canadian car I'm buying a chip for it well that make a difference ??? Or is there something else I gotta do to be able to go faster ( I have the digital dash when I switch it mph the cars speedo said 160mph as a top speed and in km/h it said a petty full 188km/h and soon as I hit 188km/h it well stay there it's at higher rpms too is it something with the tranny or the ECM ???

InfernalVortex

iTrader: (4)

Stop being an idiot. Top speed is what it will hit in a 1/4 mile drag strip. Otherwise you need to be at least close to posted speed limits. You're gonna get people killed.

TysonNorthcott9

Im going to racing on top speed strip ... Which a 3/4 mile strip

rusty vango

I have seen 140 in my 86. but its got a 2:73 gear

Restrorob

iTrader: (7)

Back in the early '80's (a young buck) I took my 70 bird past the 160 mark, I cringe every time I think about it (Ole geezer) now. I could'a killed myself and others......

Base91

iTrader: (1)

But you're still here! Depends on where you are and what the traffic is like. In parts of Europe used to cruise well over 100mph. And in Germany you often have to get out of the way of guys that can afford to go much faster. It's not the speed that kills it's the sudden stop.

rusty vango

I do my runs very early in the morning. when there is less traffic and cooler air.i have a calibrated speedo and GPS. to check by.best run so far 147.

RedLeader289

iTrader: (2)

The difference though is that their roads are made to sustain said speeds of 100+, ours aren't and aren't maintained to either. One pothole, bad joint, heck...even a patch of dirt on the blacktop, at 100+ is trouble.

Base91

iTrader: (1)

Not all roads here are crappy. The conditions need to be acceptable. Includes road, car driver etc. etc. Some roads around me aren't good for more than 25mph!

Restrorob

iTrader: (7)

It was around 1am when I pulled this stupid stunt and it was here;




It's 2.8 miles long and the span is about in the middle, Got off the throttle at the top...... I had two passengers that didn't believe that ole bird would fly......

Reid Fleming

iTrader: (2)

RBob has the most correct information.

In terms of TPI cars with the 245/50/16 Z-rated tires (Goodyear Gatorbacks), there was no computer top speed. Just a transmission top speed. Manual transmission top speed being simply as fast as the engine will push it. Automatics on the other hand had a few different options.

All the automatics up to 1987 would let you run flat out. In 1988, the automatic was strengthened somewhat. But they also changed it so that you can't hold WOT in 4th gear. It will downshift to 3rd at aprox 66% throttle. This means that your typical TPI 305 or 350 automatic with the good tires and a 3.23 or 3.27 axle ratio will top out at around 120 mph. It won't stop accelerating at that point. But it will continue on in 3rd gear up into the red line and then some. Most of us don't want to be doing 6000 RPM in 3rd gear with stock valvetrain. So basically 120 mph is about what you're stuck with.

I've gone into detail about the hows and whys around the top speed runs here (post #11):

https://www.thirdgen.org/forums/tran...3-4-shift.html

InfernalVortex

iTrader: (4)

There's a huge difference between going 100 mph on the autobahn (Which is designed and built much better than the Interstate Highway system) where people EXPECT and watch out for cars going that fast and doing it here in the states.

TTOP350

iTrader: (8)

My 89 formula 350 pegged the mechanical stop on the speedo which is 5mph over 140mph and it was still going.
I've been 240mph in a ford GT I modified.

akanitro

iTrader: (2)

Damn T-Top. I've only been 214mph in a UGR Lambo and 234mph on a turbo busa. You have me beat by a long shot. I need to step up my game for next year's TX2K15 event.

Carl Ragsdale

I have a 1989 with stock 305 .140,000 original miles. My top speed averages 122

Drew

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