ok so i was at the junkyard today looking for a 455 and came across an engine sitting there and itwas definately a BOP. now i'm really set on finding a Pontiac engine for my car not a buick or olds. The block was surface rusted pretty bad and i couldn't find a cating number anywhere there was only a casting number on the intake manifold and the date it was cast 10.29.74. Removed the intake and the valley pan in hope of finding out which displacement it was a 350, 400, or 455 but couldn't find a number at all! The only thing that was cast in it was C1. So now i'm thinkiong it may be a buick or olds as i'm not as familiar with the two :S Turns out also there's chunks out of the block inside around the crank so it dfefinately can't go in the car but i was thinking i could use it as a mock up.anybody know? thanks

 

It's hard to describe each one but if you had pictures I could tell you if it was a BOP or Caddy engine.

I was never a fan of the Buick engines. Lots of people like the Pontiac. Out of the three choices, I'd build an Olds.

 

nope no pic sorry but i was also wondering somehting else. I know the 350 the 400 and the 455 all used the same block but i was just wondering where the differnece in displacement comes in? is it just bore and stroke or something else?

 

the blocks are diensionally identical ( or so close it's not worth measuring) the 350 & 400 have the same main bearing size 3", but different bores. ALso, you caint bore the 350 out to a 400. THe 455 has a main bearing size of 3.25".
The .030" overbore on a 400 will get you the standard bore 455. CHeck the sides of the block for a casting of the block size. Also,, peruse the Poncho V8 swap sticky for more info on the Poncho blocks

 

not a thing on the side of the block but i think i'll head back out to the yard tomorrow and get some pics of it so i can post them