By David K. Wilson
Originally, my '96 Z28 came from the factory with a T56 (6 speed) as I'd ordered it. I love the additional driving experience of shifting gears. From '96 till the summer of 2000, I had rowed the gears and loved every minute of it. However, expensive clutches are the ONLY option you have for the LT1 F-Bodied cars and I had to replace mine after only 23,000 miles. I spent $500 (plus tax) at MTI for an RPS Turbo Clutch and dropped another $525 for SLP's lightweight (13 pounds vs. the factory 20 pounder) Flywheel. One summer night of street racing in Houston in 2000, after vanquishing an LS1 SS, my third gear synchro started grinding on all shifts unless I took a contrived effort to avert the crunching. I told myself that I would fix that someday soon but drove it like it was till August of 2000. At that time, I'd gone to the local 1/8th mile track and was going thru time trials. On my second pass of that day, I power shifted to 2nd, only to be greeted by what seemed to be a missed shift. I quickly reshifted and floored it again. Once again, the motor bounced off the rev limiter with no forward motion. I got out of the throttle and stared down at the shifter as the car idled down the rest of the track. I deliberately shifted to 2nd, let out the clutch slowly and pressed the gas pedal. The result was that while the shifter detents made it feel like it was in second and there wasn't any grinding/notchiness, the RPM's would rise and fall as if the shifter/tranny were in neutral. Second gear had literally disappeared....
As I drove home to Austin from Sealy's track afterwards, skipping over the now impotent 2nd gear, I was assessing my options. Rebuild the T56, put in a new clutch, get a new flywheel (my old clutch was all but worn out and the lightweight flywheel was NOT the ticket for drag racing) ? OR..... convert to an automatic? All the successful guys in my car club seemed to be running Automatics with high stall torque converters. Plus they were consistent. Next problem..... The 4L60's and 700 R4's with the very desirable overdrives, are expensive to repair/rebuild and prone to breakage (Before flaming me, I have a long list of fellow Houston/Austin Fbuds with multiple broken trannys to refer to). The other option was to go with a TH350. Strong, light, INEXPENSIVE.... Heheheh...) Of course, they don't have overdrives by factory design, but I can live with that drawback since I have minimal Highway time on my daily driven Z28.
Two friends of mine (John Benton and Emil Dusek) had trail blazed the swap weeks or months before me and gave me all the tips, gotchas and watchoutfors that I needed.
Parts:
TH350 tranny ('65 to '72 year models I believe) with a 9" tailshaft(uses stock driveshaft length/yokes)