C4 tranny

[ScreamingMimi]

Hi - doing the much bally-hooed I6 to V8 swap in a Sprint 66 Mustang - no problems till i got to the bellhousing/flexplate. Had a 133 tooth flexplate - swapping to the 164 tooth. found out belatedly that the transmission shaft is the smaller of the two - it wobbles when inserted into the torque converter. I am having difficulties finding the right torque converter since i would like to avoid switching trannies since the one i have is in prime shape - any ideas?

 

[TOM B]

THE SMALL SHAFT C4 IS 24 SPLINE. you should run the 157 tooth flywheel with 10.5 bolt pattern. I dont think the larger 164 tooth will fit into a small c4 bell. Both TCI and B&M make good converters but I would go with a TCI for more of a selection for the 24 spline 10.5 pattern. I run a 24 spline shaft with a Tci 3000 stall converter on a TCI 157 tooth performance flex plate.

 

[65straightsick]

Or go for the T-5

 

[ScreamingMimi]

I have the larger bell already - I just want to use my smaller spline with the 164 since it is the flexplate that was originally matched to my 302 that I am dropping in. Worst case scenario - I replace the tranny - I thought about the T5 but I am on a doozy of a budget. And around here, classic mustangs and parts are HARD to come by unless you order out of a catalog and that takes more $ than I have to fork over. By the way - will the 302 manage with the 157 flexplate or do I have to stay with the 164 for strength?


1966 Sprint Mustang (no more!)
302 out of 71 Torino
One woman restomod!!!!

 

[TOM B]

Im running about 450hp through my setup with no problems. I have the small shaft and a tci 157 tooth flex, 3000 stall converter. more teeth dont make the flex stronger, just buy one thats for racing, there cheep too.

 

[ScreamingMimi]

GREAT! I will go back to square one and find a 157 with torque converter - much easier than swapping the entire tranny - i can use the same bellhousing and everything should bolt up nice and tight - THANK YOU!