I put a T-56 out of a 1994 Z28 into my 1985 Iroc-Z about two years ago. I bought the centerforce flywheel for a 2 piece rear main seal and bought the Spec stage 1 clutch and all new hydraulics. I had a problem from the beginning, but I'm not sure what it was. The pedal has always been soft but it shifted fine. I had some grinding after about 5k miles so I pulled the tranny to see what was going on. I found that my clutch was nearly whiped out and my clutch master cylinder was destroyed. I bought a new clutch and resurfaced the flywheel and got a new master cylinder. I installed everything over the weekend and the pedal feels better but still maybe a little soft, but my biggest issue is NO REVERSE! I had reverse when I pulled it into my garage, now there is nothing. The only thing that I really changed was that I tried to line the master cylinder up with the pedal a little better by shimming it at the firewall where it comes through. I was worried that was my reason for the master cylinder to go bad in the first place. All the other gears work fine and shifts smooth, but it just acts like there is NO reverse. It slides over where it needs to but it acts like there is nowhere for it to "click in". If you have ideas about anything that might be going on or have seen this issue before please let me know.

I am also kind of curious if the "Clutch MC Rod modification" would help me or if I need to do it? Please let me know if you have ANY suggestions.

Thanks for all the help!!

 

If you can move the shifter to the REV gate ok, but there's no reverse, it's possible that your reverse snap-ring has broken. Although it doesn't fit in with anything that was happening to your clutch/pedal/etc., it could have been weakened by having to overpower the fork when you were having clutch problems..

You can pull the tailhousing of the T56 while in the car. So as far as repairs go, it's one of the better things. Just have to drain the fluid, pull the shifter, driveshaft, Xmem, and take out the 8x 15mm bolts that attach the tailhousing to the maincase of the trans.

Snap-ring is in the lower left corner in this pic:

 

FWIW, I saw this on the ls1tech board about no reverse after a clutch install, although his issue is with the clutch dragging so much that it won't even gate into REV..

http://www.ls1tech.com/forums/manual...rse-still.html

If you can get yours over past the REV-lockout solenoid and into gear, it shouldn't be a clutch issue any longer...

Also, I thought some more and a broken snap-ring won't keep Rev from engaging, it will keep Rev from releasing.. something odd going on with your shift linkage..

Did you make sure the shifter cup inside the trans wasn't broken when you put the shifter back on, and make sure the shifter is bolted down tight?