Want to change to synthetic oil in my 500hps any advise as to anyones recommendations. I was advised that Royal Purple was a good choice if so is there different grades and what would be the best? Thanks

Mobil1 15w50 and Napa Wix Racing Filter 1061R; best combo out there.

I always substituted a 1 quart bottle of Lucas Oil Synthetic Oil Treatment for 1 quart of oil as well.

I've always used Mobil1 15w50. Mobil synthetic base stock is used by most of the other synthetic manufacturers, including royal purple and amsoil.

Ive always used royal purple race 51 in my motors and 75/w 90 in my drives and napa racing filters. have 400 hrs on my hp500s and still run like new and oil pressures are still as they were new. i change the motor and drive oil every 20 hrs.

I am using Mobil One V-twin 20w-50. So far I am having good
results. Each oil change I send a sample to Blackstone Labs
for analysis. So far virtually no wear on my 496 HOs.

where to get this vee twin mobile

http://www.joegibbsracingoil.com/

I've used Mobil One 15w-50 in my last three boats with no problems. My engine builder said to use Mobil One (Innovation) so thats what I'm sticking with. Royal Purple is also good. I use their gear oil in my drives (Konrad).

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