They've sent me a rebuild tech sheet for holding up to 700hp. They have valve bodies for full manual shifting as well as transbrakes. He quoted me 1800 AU for a built tranny plus shipping. I can forward the tech sheets to you if you want to have it looked at by a shop. I also have a shift improver mod sheet that I can send over.
Bernard, I've thought about this for a few days, and I may be able to help.
A larger servo would help (like Corvett servo for th700r4). Also, getting as close
to minimum clearence as possible in direct clutch pack. I never modded a jatco,
but I've modded tons of TH 350, 700r4, and c4s. You can also play with the accumulators. Shorten springs, lenghten springs, spacers. If I had more information, I could give you some more direction. Could you send me the tech sheets? I'm also interested because I own a 280Z with an automatic.