Category: Pontiac

Discover the differences between small main journal and large main journal Pontiac V8 engines. Pontiac’s V-8s were all small blocks, sharing the same connecting rod length 6.625 inches, except for the later short deck 301 CID and 265 CID. Learn which engines used smaller main journals, such as the early 287-370 CID engines and which used “large” mains, like the 421 CID, 428 CID, and 455 CID engines. Find out more about each series of V-8s by clicking the image links. All Pontiac V-8s were phased out in 1981.