Running Castrol 5-50 full synthetic. Great for San Diego since it never gets that cold.

 

Yes, but it's been a while. I used to use it in my RX-7's (all three generations) and can say one really great thing about it. Mazda's rotaries all use oil injection in the rotor housings to lubricate the surface that the apex seals ride on as well as relying on some blow-by from the oil seals on the rotor side to lubricate the side seals. This inevitably results in some carbon buildup etc on the rotor and side housings. It's rarely an issue in a torn down motor, sometimes causing side seal sticking, but the street and track engines that had been run on Redline had a lot less carbon built up in them. I can't compare to other synthetics because a lot of older Rotorheads had embraced a peculiar religion that running synthetics increased the rate of carbon buildup. Redline was magically immune, apparently...

 

I use Motul 15w-50 300v and saw higher bar readings on my oil pressure gauge and cooler temps compared to Mobil 1 15w-50. This has made me a believer in the switch-over

 

15w50 or20w50