Topout or Govener

[89IROC&RS]

Originally Posted by Morley

They are WRONG. I have been burning 3rd gen chips long enough to know that the ECM does limit the speed. There were NO 3rd gens made with the 4L60E transmissions.

darn it morley, you beat me to it. you can easily tell the transmission does not limit speed, because the RS which is limited to 115 uses the exact same 700R4 as the IROC which is not speed limited (to my knowledge) and also, how would the manual transmissions automatically kick back to limit top speed?

[flatlander757]

Originally Posted by Rally Sport 92

What they dont look at is that in those days the 4 speed was the 6 speed of today.

damn straight! they didn't NEED 2 more gears!

[instantkevin]

Originally Posted by 89IROC&RS

darn it morley, you beat me to it. you can easily tell the transmission does not limit speed, because the RS which is limited to 115 uses the exact same 700R4 as the IROC which is not speed limited (to my knowledge) and also, how would the manual transmissions automatically kick back to limit top speed?

Okay... I have driven my car to approx 130mph downhill in overdrive. and i have never experienced fuel cutoff, even though it's supposed to be limited at 115mph. This is why I say there is no computer limitation in 3rd gen trannys. And to my understanding the 700r4 limits top speed by not allowing full throttle engine operation in overdrive. it kicks back down into 3rd gear when you hit 75% throttle. and obviously, if you are in third gear you can't go as fast as you could if you were in 4th gear.

the trick here being that the car will not accelerate without more than 75% throttle in overdrive, but when you do more than 75% it drops you back to 3rd gear, thereby limiting the speed to approx 115mph. And the TCI throttle valve will allow this percentage to be changed. just as www.transmissionhead.com has a valve that does the same thing.

The only device in the 700r4 that is computer controlled is the torque converter lockup. And if there is no fuel cutoff (as it seems to me), there is no way for the computer to be the limitation.

So if yall know something that I do not, I would like to know. TCI nor TransmissionHead show that the 700r4 is computer limited. Nothing I have read says it. And from what I have experienced, there has never been fuel cutoff. Morely, IROC, Please explain.

thanks.

(by the way, i never said 4l60e came in a 3rd gen, I was just sayin that TCI is saying that 700r4's and 4l60e's are limited the same way, cause they both use the same TV valve to allieviate the problem).

[x8xViperx6x]

Alot of older cars have the speedometer that only goes up to 80 mph but I KNOW for sure they are capable of going just ALITTLE faster than that......

[Mr. Luos]

Mine goes to 150. I can go faster than that if I wanted to.

But I would kill myself, I know better.

[Morley]

Originally Posted by instantkevin

Okay... I have driven my car to approx 130mph downhill in overdrive. and i have never experienced fuel cutoff, even though it's supposed to be limited at 115mph. This is why I say there is no computer limitation in 3rd gen trannys. And to my understanding the 700r4 limits top speed by not allowing full throttle engine operation in overdrive. it kicks back down into 3rd gear when you hit 75% throttle. and obviously, if you are in third gear you can't go as fast as you could if you were in 4th gear.

The transmission is not computer controlled other than the TCC lock up. Speed is limited by turning the injectors off in the PROM programming. If you've been to 130 without fuel cut off happening then either 1) You have a car that came with VR+ speed rated tires. 2) Your chip has been reprogramed/replaced. 3) Your speedo is off at higher speeds. Those are the only possibilities.
As for the 75% throttle in overdrive...I had better be doing one hell of a lot more than 115 in 3rd. It isn't in the valvebody, it is a little plunger device that you can modify so you can be in 4th and WOT. I wouldn't do this unless you want to burn up your trans since the fluid isn't lubing the trans enough in OD to run like that (GM designed it that way). There is a way around it though, it is called a "full time lube" mod and most performance rebuild's have this done.

[89IROC&RS]

also, something to keep in mind, is that overdrive gears do not have the same torque as other gears, thats why with the T56 transmissions, top speed is found in fifth gear, because sixth gear dosnt have enough power to match the speed of the fifth gear. thats why in quarter mile drag racing, you want the transmission in drive rather than overdrive, because once it shifts into overdrive it will be accelerating slower than if it was in 3rd gear.

[Rally Sport]

Originally Posted by 89IROC&RS

also, something to keep in mind, is that overdrive gears do not have the same torque as other gears, thats why with the T56 transmissions, top speed is found in fifth gear, because sixth gear dosnt have enough power to match the speed of the fifth gear. thats why in quarter mile drag racing, you want the transmission in drive rather than overdrive, because once it shifts into overdrive it will be accelerating slower than if it was in 3rd gear.

Very true, my neighbor who has a 00 Z28 says his 5th gear is better than his 6th and has gone around 150, racing a Vette or something, I forgot.

[instantkevin]

I did replace my computer with an aftermarket one, only because I needed to. And i had H rated tires.

What is the process on the "full time lube" mod?

Sounds like I need to do this. I'm putting a trans temp gauge in my 700r4, so i'm not too worried about burning it up. It will warm me when temps start getting high.

And so, IROC, how does the 700r4 that is not limited do it? Can I just pull the valve body out of that one and use it?

Anybody know what my top speed will be in third gear? I know I can calculate it, but just curious if anyone knows.

[Rally Sport]

You should've gotten a different tranny since you were changing the engine out, ya know?

On another note, I just got back from driving my bro's Jeep and my first manual lesson, man this shit is freaking fun and hard compared to auto, cause auto you just gotta hit the gas! Needless to say I did pretty good.

[89IROC&RS]

the 700R4 that is not limited operates just fine because the computer dosnt cut fuel to the engine..........

[instantkevin]

Rally Sport 92, I did get a different tranny. the swap can't be done without the V8 tranny.

Morely, got any info on the full time lube?

[finalturismo]

Originally Posted by Rally Sport 92

I live in TX, this highway is awesome but I dont go on it anymore because if I race on it is has to be like 60+ from a roll which is real bad for a 4 speed auto. Plus I found out when my tranny shifts its gears so I let off the gas and hit it again so it shifts like a manual, won LOTS of races because of it

its because it down shifts i done it with my cavalier befor