The older chevys before '55 had a enclosed driveshaft that was factory riveted to the rear end housing. Its called a Torque Tube drive. The prop shaft rides on brass bushings inside the torque tube. The front end of the enclosed driveshaft bolted to the back of the transmission. This transmission/b-housing won't bolt to any engine '63-newer. The 216s, 235s and 261s will fit the bellhousing. So you can swap 235/261s out and retain the transmission and rearend. The 55-62 vehicles w/235 have open driveline (the R/E you're used to) but similar bellhousing/tranny. So 55-62 vehicles can retain the same rearend when swapping engine/trannys.

Later straight 6s or any V8 will not bolt up to a pre-'55 chevy. So if you change from 235 to a V8, you change transmission. If you change transmission, you've got to change driveshaft and rear axle. This is why engine swaps into a '55-older chevy require complete changing of the running gear from engine to rear axle.

chip

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