I think you have that backwards. 904 parts go in 727 and Chevy.
John Cope has a YouTube video of a 904 that holds 900-1000 horse.
The weak link is the case not the design.
Turbo 400 have problems too. Do a burnout in 2nd gear and you,lol break the sprag. And if conditions are right there drum can explode too. This is my friends pro trans 727 that he just had done.
Heavy Ls car with new hemi. Runs high eights. Notice 904 parts.
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