What all does everyone use for a max. rpm for the 72-73 cars? Do you stick to the recommendation of 7300 or ...?

Since you can remove the rev limiter or modify it, what is a safe engine speed? Among other things, the connecting rods are 60 grams lighter than those in the 2.2 S's. When does valve / piston interference become a problem?

I think I remember reading somewhere that a piston speed of 2500 feet per minute is a max?