Originally Posted By: 02zx9r
It is a Grp III, and is over priced for the marginal performance
Actually, its not. RP is Group IV PAO base (mostly). The fact that PP is just a group III (not even XHVI "group III+" base stock like RTS) is one reason I don't use PP. Its still good oil and cheaper than a Grp IV, but I don't see the attraction of a group III when RTS XHVI (III+) is out there- assuming its suitable for your application. For other applications, PP doesn't seem enough better than PYB or VYB conventional oils to justify it to me.
As for RP- I use it in ONE application. I have a fairly big flat-tappet cam in a 440, and with its fairly tight clearances and HV oil pump, I find that RTS (only available in 5w40) kicks the high-RPM oil pressure higher than I like to see- I'm concerned about wear on the cam/oil pump helical gears and possible failure of the intermediate shaft. Most non-boutique synthetics are now SM rated, and while I actually think that is *fine* for flat cams, I'm cautious enough to prefer the added safety margin of an SL oil or an SM HDEO. The SM HDEO is ruled out due to the 5w40 rating; therefore, I picked SL rated RP 5w30 and it is working very well for me. Yes, I could use Redline or Amsoil, but RP is extremely readily available for me, and that's a benefit too.
I consider the above a fairly rational assessment- I'm not shilling for or against RP. Just using it where it works. Yes, they've made what I'd call bad advertising decisions (though nothing as bad as Castrol .... Jimmy!). Yes, its a goofy color. Yes there are cheaper options for many... but not all... applications. But its good oil and there are UOAs are on here to prove it.