[Toivo]

This is something I've always wondered about, but no one could give me a straight answer.

400 SBC's had siamesed bores, and big problems with distorted bores leading to blown head gaskets because of them.
Steam holes were introduced into the heads to try to combat this problem, but it was/is still a problem.

What is there about the Ford siamese cylinder design that lets it be used on the street without similar problems?

Thanks