[Bob Mulry]

Originally Posted by Myron Piatek

I read a dedicated article comparing rear end efficiency in one of the old car magazines a long time ago. Of the rears that I remember they tested, this was the order of efficiency:

1) GM 12 bolt
2) Dana 60
3) Chrysler 8 3/4
4) Ford 9"

I believe it said that the biggest factor is the placement of the pinion in relationship to the ring gear. The higher the pinion (closer to center), the more efficient it is. The 9" has the additional disadvantage of an extra pinion bearing.

I don't recall what others were tested.

Somebody makes/made a 12 bolt style center section for 9" housings. Was it Jim Kinnett that had a 12 bolt or a Chrysler 9 1/4 rear in his SS/AA Cuda?

Hi,

Strange still manufactures an aluminum 12 bolt drop out center section that fits into a 9" Ford housing........

I wonder if that will pass tech (HA HA) for a GM Stock Eliminator car?????

Just sayin'