I was wondering if there's any sites that could give me some info on the small block 915 and and any other small block heads? I have a chance to get a set of S.B. 915-A heads,( I know that the HOT ones are the J and the X heads). My dad's been looking mostly for the big block parts ( 'cause that's what he knows ), but I've been looking at the small blocks ( 'cause that's what I know ) and I'm needing some info on what's hot and what's not.