Wix 51515R vs 51515 Filter?

The Wix 51515R filter states on the box that it is NOT FOR STREET USE.
What is up with that being that I have a Hot solid cammed street/strip motor and intend to use this filter?
I think it has some thing to do with the by pass valves or the amounts of filtration being to much on the R filter, am I correct?

So for a street/strip motor like mine where it will game the strip a few times a year, I should use the non-R filter?
Best told me that they like the R filter for their motors. I'm going to give them a call tomorrow and see what fits.

for what its worth my machinist said for a good bracket motor he prefers the standard Wix because of better filtering only uses the R filters on all out race stuff.

Does anyone know if the R filter has a bypass.....

Running high oil pressure with thick 20/50 oil that is what concerns me the most.....

I have a K&N on mine now and have used the wix with no issues.

jomar performance makes one with no bypass