Attention: TDR Forum Junkies 
It is generally accepted that you can run these engines as far up as 3300-3400 MAX without the need to go to the heavier 60lb valve springs.
You must however, make sure that you have a good, accurate valve set at that level.
BOB.
You must however, make sure that you have a good, accurate valve set at that level.
BOB.
