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.
