Thread: Getting a shift kit

In stock form these transmissions are fairly sloppy and things start breaking around the 300whp mark, but GM racing uses them in their 1200 HP sunfire race car and there are several of them running 9 and 10 second quarter mile runs by the big vendors out there. After a few parts are upgraded in these transmissions they will take a lot of power no problem. You are definately on the nose about the term Shift Kit, that is a registered name from Transgo and everyone copies the name, have for years and years but that is just how it is and for people not in the trans industry they dont know any better so anything that changes shift behavior is called a shift kit. I dont even bother pushing this because I would be kicking a dead horse and stirring a lot of pots lol. Shift Kit is just easy for everyone to relate to I guess and they know what its intended purpose is. While Transgo does have a kit for this trans its not one of their better kits compared to other products though it does help out and makes a great base for package of upgrades that nobody else offers, especially the accumulator spring setup.

I do internal work in addition to the Transgo kits to make the shift firmness/quickness match the cars power levels but unless you are rebuilding the trans and the whole thing is apart it doesnt help people looking for the quick easy upgrade. For selectable shift firmness and hard shifts, if you really want that, then the best shift kits out there are from Intense and if you can find an original Thrasher/Transgo kit. They include new accumulator springs and selectable spacers with firmness levels in the instructions. And of course the cheapest route is to go with the W-body store or ZZP kit which is nothing more than spacers that anyone can buy at a hardware store and they do not include any new firmer springs, but simply act as spacers to limit accumulator piston travel but wont give the full benifit of the better kits. Pcm tuning is another way to get harder shifts, you can make a stock trans bark the tires just by doing some tuning though I never recommend this as you really have to turn up the pressure to accomplish this.

Im no fan of blocking the accumulators either nor do I prefer having to tune a car much to raise line pressure but every car is different and I like being able to tweak the shifts in the pcm. Transgo made the original Thrasher shift kit which was identical to what they offer now but had selective firmness levels, more spacers, and shims that go under the smaller springs on the acc pistons. That kit would make the tires bark on high settings. One nice thing about the pcm controlling shift firmness is that it will relearn part throttle to tame down the shifts more you drive it. After I build my transmissions sometimes the light and part throttle shifts are very harsh because of its mods but will learn quickly to this and make normally driving nice and have great WOT shifts. I never tried playin with adjusting the EPC on these transmissions and the solenoids that I have been using the last year arent adjustable like the OE delco ones because the adjustment screw is peened in so tight.