[Formulajones]

Originally Posted by i82much

Actually google is telling me you can do a 572 standard deck BBC. I'm not gonna lie, I love my Pontiac, but that is pretty tough to beat.

Yeah the Siamese bore BBC stuff with standard decks can be built pretty large. I have a GM 502 here that I'm going to do something with soon. With it's 4.470 stock bore and a little 4" crank it's already a 502. 540 is easy to accomplish with a 4.250 crank and that falls right in. Can even go slightly bigger on bore or crank or both and reach 565 or so without much effort. You start getting the wrist pin up into the ring package which bothers some people but that's been going on for decades with all brand engines and proven to be fine.

What dad did with his Pontiac was sort of the extreme on the other end. Since Pontiacs typically have small bores, and the MR1 is no different. He went with a 4.350" bore on his MR1 to leave some meat for future builds, but those things accept an enormous crank without trouble. So he bought a 4.750" crank and stuffed it in there for 571 cubes in a standard deck block.