If you think about it, even a turbo 400 or a 727 is probably overkill for say a 10 second car. Protrans puts 904 internals in the 727.
I've heard they are developing with ati a turbo 350 that also will use 904 parts.
I don’t want to muck up this post anymore than I already have but a buddy of mine that passed away several years ago ran a Chevy in super stock. His transmission cost thousands to build and had Mopar 904 guts in his three speed Chevy transmission. His car ran 8.90’s. I wish I could give more info but I can’t. Sorry for the muck job.
