My car fly's up through the gears fast but quickly runs out of gear at 120, and it would just red line until i let off.

I have an auto, and in overdrive when it hits 120....the rpm's just revv past where it should shift at, and the gear winds/runs out and i have to let off the gas or it'll cause some problems of course.

Is my top speed killed because of gearing? Or could it have been matched with the wrong tranny or something?

 

Its the gears. Sounds like you have 3.73 or 4.10.

 

Why do you need to go over 120?

 

Is it like hitting a rev limiter? I'm not sure if 3rd-gens had them or not?

Otherwise, even with 4.10 gears, 4th gear should be good 'til about ~160 mph!

 

My 92 had a speed limiter at 110

 

Because i'm young and stupid....and its fun



At about 120 i revved it to just about 6500 then let off.....i didnt hit any rev limiter or anything

Is 4th gear/overdrive maybe not working or something like that?

 

I'd say its your gearing. My 85 F-150 has a 3.55 posi rear end and 4 speed and it redlines @ about 90 mph. It was made for hauling, but to me the 4 speed kills in on a highway run.

 

If you have a 350 in a 85 IROC, your car is NOT stock. The 350 was not an option that year. Based on that, I'd say it is very possible the gears in the rear end are not stock either, and it is likely you are running out of gear on the top end due to having either 3.73 or 4.10 gears.

Watch the tach and make sure it is staying in 4th gear. Many 700r4 transmissions of those days did not stay in overdrive past 3/4 throttle. A specail part needed to be installed to force it to stay in 4th at those throttle positions. Iroc's and vettes were supposed to have that stock at some point, but I'm not sure about 1985. Also, given the non stock motor, who knows where that transmission came from. It could be from a different model car all together.

 

The 4th gens top out at 160...a 3rd gen can't pull those numbers unless theres been work done...alot. Honestly I don't think an A4 will hit 160 either.

 

Oh, I guess that's probably true, eh? Now do you mean a 3rd-gen A4 can't hit 160, or an A4 4th-gen either? I know for a fact that my car can hit ~160 even with the A4 (w/2.73's, in 3rd gear.....I haven't actually tried w/4.10's).

 

Well a 3rd gen I don't have a question...I do not believe it will hit 160 totally stock in an A4. In your 4th gen with 2.73s I'd believe (because of gearing) with the 4.10s I'm not sure if you'll make it that far. Since you have an M6 you have a far better chance than an A4 does.

 

I know the 'vettes of around that year had the 4+3 tranny. I don't think it was a 700R4 though. If you only have 4 gears, that I know of there wouldn't be an overdrive. You just have 4 strictly accelerating gears. That makes sense to me. However, if you line up your shift points right, you will accelerate pretty hard in an overdrive gear too. If you have the power, which a 350 TPI should. That's a good strong motor.

What is the top speed of our cars?

~Paul~

 

I taped 120 at 3/4 throttle last night by accident (trying to keep up with a Yamaha 04 R1), still had a lot of RPM to go and pedal movement, A4 2.73's

 

In an older 700 R4, the transmission will not shift into 4th gear above 1/2 or 3/4 throttle. I can't remember which at the moment. It's designed that way to keep you from tearing up the tranny.

 

Well, i had an 87 Monte SS with a 355( not stock) and a 2004r tranny with 3:73 gears and a shift kit, and i pushed my car to 140mph and could have prob gone a little higher. So that being said i am sure that his car can hit the 150 mark...with 4.10's it will be hard though thats alot of gear back there. But in my monte i didnt even have an ECM never mind a rev limiter...or govenor...so i am sure thats prob what it was in your car.