It is about the spring pressure , rpm , lobe opening rates and how much cyl pressure the exh valve is opening against .
There are good gains in the push rod by increasing the wall thickness , but more gain in a bigger tube dia . The .080" wall 3/8' units will do a lot of engines...what do you have ?
as of now i dont have any, I just was looking at my heads that i bought a while back, and noticed that it had 3/8 guideplates, and was wondering if that would be ok for my build which is going to be a 521, with hopefully 600-700 hp.
Hey, I pulled my motor apart and my antique pushrods from the early 90's are all cracked at the tops so now I need new ones. Do I need to check lengths or just get a new set, can't remember what I had. Motor is a C9 block decked with Blue Thunder ford port heads. The old ones are 3/8 hardened but just old. Chris