Comp Cams...trouble in paradise?

Old Man Mopar , Yes the 350 was same block as the 400 .

Yep... Actually all Pontiac V8's from the 287 all the way to the 455 (except the late 70's early 80's 301) were the same size block. The only way to tell them apart was to look on the side or under the distributor to see what size it said it was. People called all of them big blocks because of their large physical size