Originally Posted by curtis73
Swapping a roller cam into an old block costs a lot. Machining a 2-bolt block for 4-bolt caps is cheap. Not to mention a 2-bolt block will take a good bit of abuse. I'm running a 2-bolt right around 430 hp and I don't worry a bit about it. 116k miles with no issues.
Roller cams are super nice, but retrofitting one is expensive and not worth it. Go with the roller block. If you need 4-bolt mains, have it machined.
Tell the guy in the link I posted its not worth it!!
And I wish I could base all my info on one block that has gone 116K miles with no issues.
Why the hell did GM even build a 4 bolt main block
Here is a another good link.