hey guys I just recently purchased my 4l80e for 2000 z/28 and I wanted to find out what would be the best shift kit to put in it, I have been thinking about getting hd2 shift kit from trans go. And around how much horsepower will the transmission with just the shift kit and a 3600 stall(yank pro series)

 

I have seen them hold 750 - 800 FWHP without any problems on late style transmissions with just the TransGo 4L80EHD2 and the addition of the 2004R cup seals on each side of the center support bolt. On late units you do not need to add the "blow off valve" that comes in the Shift kit. Drilling to the right size feed holes in the separator plate to match the torque converter stall, weight of the vehicle, how you drive, etc.

 

PBA is right. Be conservative on the feed hole sizes and don't go larger than what is indicated in the kit. 80E's make good pressure already and it's easy to over-drill the holes and have harsh shifts that will over time damage the internal transmission components, and also damage the rear diff, axles, carrier, & u-joints. You don't want it screeching the tires when it shifts. The internal rotating components in an 80E are NOT light. If you set it up to shift too firmly it can drastically shorten the life of the trans, your rear differential, your axles, your U-joints, etc;