All righty, you guys have always been helpful, one more time for me.

I have a 396021F – 1968–1972 all 455 engines. “E” headsblock in my 1970 442 currently and would like to replace the TH400 with and 200R4 transmisson.

My car is in storage away from my house and I have a line on a decent trans, but would like to verify the bolt pattern measurements for the back of my engine to be able to match the 200R4.

The guy is more than willing to compare the measurements, but I have no way of doing them at this time.

Does anyone have, know or is able to make measurements of the center to center bolt patten for me.

Thanks,
Steve

 

This is a pretty easy swap, the trans will bolt in with no cross member modifications. Might require some minor cooler line bending to get it to fit. Use a driveshaft from a TH350 car, make sure the shifter will work correctly (is it a factory shifter? If so, Shiftworks makes a shifter conversion kit that work well) and make SURE the TV cable is connected and adjusted properly! I did this conversion about 12 years ago on my 69 Olds, it really is a simple swap.

 

No measurements required. Every GM V8 from the mid 1960s -up except Chevy and Northstar use the same BOP bolt pattern on the bellhousing. Nearly every 200-4R ever built has both the BOP and the Chevy patterns on the housing (there were a few early trans cases with BOP only).

 

And, unless modified, I'd get one of those diapers to wrap around it, so when it blows, you don't get ATF under the rear tires!
Had one behind a 305 - lasted 92k, even though I 'babied' it, with no torque.
In stock form, might last a month with the torque of your 455!

 

You guys are awesome and always come through.

Thanks !!!

 

The turbo Buick community has found and fixed all of the weak spots in the 200-4R. Contact one of the transmission specialty shops who build transmissions for GNs. CK Performance is one that I use, but there are others.