Are the dimensions on the 904 and 727 torqueflights the same? Meaning are they the same length front to rear? Also, are the output shaft splines different ( larger/smaller splines, different number of splines etc)? Would it be possible to use the same output shaft from my 904 in a 727? Curious about this because I am switching to an 8 3/4 and want to use the large u-joint driveshaft. That would mean using (most likely) a 727 output shaft from a V-8 car. Anyone have any idears?

Thanks,
Jesse

Believe the 727 is longer than the 904. Also, the output shaft splines of the 727 are larger in diameter, so a 727 slipyoke usually doesn't fit a 904.

You can get a "conversion" U-joint that is large across two caps and small across the other two caps. Don't worry about U-joint strength; they're plenty strong enough, even the small ones, if you buy a quality brand.

I have used the conversion U-joint on mid 12 sec. drag cars with-out any problems.
DD