Solid flat tappet with EDM tool steel lightweight lifters and you’re good to go to 7500 rpm at a fraction of the cost of a roller.
I have NO IDEA why guys try to run race
mechanical roller profiles on the street.... the criterion I attach to "race" Roller
profiles being those requiring 550 Lb per Inch V/Spring rates ?
Because, and very simply here.... it is the V/Springs that typically go "soft" over time in the "street" environment when using the RACE Mechanical Roller Cam profiles ?
.... which then invariable is the root causes of Lifter/Rocker and other FAILURES in the "street" environment.
the "street" Roller M
echanical Cam designs..... that just don't make diddly extra power over a well selected Mechanical Flat Tappet anyway ?
so WHAT's the F**King POINT ?
So for clarification here ?
There are 2 Kinds of "Mechanical Roller" Cams.....
those profiles designed for Track/limited usage, and typically indentified by Requiring V/Spring Rates of 550# and HIGHER ?
those profiles designed for extended street
driving and usage, typically identified by sub 500# V/Spring rate requirements..... but that just do NOT make didly "extra" power over a well tuned/selected Flat Tappet ?
And for all the wing-nuts who READ David Vizards book and believe otherwise ? you just carry on, believe whatever you want and do as you please.
And for the OP ?
If all you are looking to do is 650-670hp ?
WTF do you need a Roller anything for THAT ?