Quote Originally Posted by Supercharged111 View Post
I think the zinc is still good for rockers that don't have roller tips too. I believe the M1 is a group 3 or 3/4 base stock whereas the RP is a group 4 base stock. I know M1 runs on the thin side because I have researched that one. Their high mileage oil has a smidge more zinc in it, but not enough to be a racing oil. RP isn't a racing oil either, but it is supposed to be better than M1. I think when people think of a racing synthetic they think of a group 5 base stock oil. Those are what initially debuted as a synthetic oil and are the ones you have to open your wallet for the most.
RP does make a line of racing oils.

Sorry for taking this thread so far off topic!


JJ