My car has one and I have no idea what it does. I actually think it hurts my car since it doesnt let it go into 5000 rpms. I ran a 15.2 at 88mph in my 87 Camaro 5.7 liter. I think thats slow

 

NO ONE knows what it is. I have a 700r trans with shift kit

 

How do you know it has a shift kit? Word from previous owner? Receipt?

There are several shift kits out there.

The BBK is considered one of the worst as all it really does is boost line pressure and make shifts very firm, but huge amounts of driveline shock, even at partial throttle.

And then there is the regular benchmark, the Trans-Go shift correction kit. If its installed right you can have butter smooth part throttle shifts, getting progressively firmer as the pedal goes further down. These actually ease the stress on the trans during shifts.

I had a trans-go shift kit, .500" boost valve, vette servo and I think one other thing installed in my trans on a stock rebuild and it improved the 700r4 tremendously. I'd recommend one to every one who owns a car with a 700r4.

BTW, my first run in my GTA with a peanut cammed 350 TBI long block netted 15.3 @ 87mph at Route 66. I have a video of it somewhere. I miss driving my car though.

 

I have recepit when it was rebuild. It does shift firm

 

What does the receipt say, otherwise you'll never know what kit is in it.

BTW, rather than posting a 2 minute google search would have turned up far more detail.

http://www.transgoperformance.com/faq.html

 

I got a 2200 STALL/PERFORMANCE SHIFT KIT

 

The Shift kit is not preventing the shifts from going higher. The TV cable must be "tight" at WOT. If the Tv cable is loose, then the WOT shifts will be down in rpm. If it is tight, and the shifts are down some in rpm, then you night need to go with a governor kit so you can tailor the shifts at WOT.