As the sooth sayer im not clear on it either. Buick has its own nailhead bolt pattern up to '63 then it had a 1 year pattern in 64. it was a 1 year 400 trans with switch pitch torque converter.(round bell.. no "cat ears" like the BOP) 1965 would be the first BOP bolt up. BUT.. i think the small buick nailhead used the old bolt up?? (some did????) "O" used the BOP in the f-85 line in '64 (NO thats not a power glide) but the full size cars were the old bolt pattern,( this bolt up..olds V-8 thru '64 394 and cadi) the big olds didn't get the 400 switch pitch till '65. the '64 had the new engine..330CI and big O didn't get the new engine till '65. it used the 330, 425 and 400 in 442 only. "P" may have been the 1st to use the BOP bolt up. I'm not sure when, but i remember a 4 speed change out on an early pontiac with the BOP. (may have been changed out before i got there) not sure because "P" didn't have an auto trans with the BOP till '64 OK....maybe i just confused the issue. but thats how i remember it.
Looking at your motor mounts I see why you chose the Unisteer and I can see where it'll give you room for the exhaust. Why didn't you design a Hurst saddle type so commonly used for the SBC? There might be enough room for the headers and steering. Now I get it!
The Jalopy Journal
