So I've been doing some testing lately, as long as some pretty hard running. 502MPI, 465hp dynoed, running Mobil V-Twin 20-50 this season with the Merc Hi-Performance oil filter. Previously running Brad Penn 20-50 and the Merc filter. Cold oil (75 deg air temp) I'm seeing roughly 50 psi oil @ idle. After running hard and monitoring the oil temps/pressure, i'll see roughly 50psi @ wot @ 210 degrees. The hotter the oil gets, of course the less pressure my motor will sustain. I was running momentarily at 240 degrees and had the psi down to roughly 40psi. When I back off, to roughly 4000rpm, (from 5,200) the oil temp drops to about 230 and i'm back to about 45psi.

To be honest, I don't exactly remember what the brad penn oil ran for temps/pressures. I just figured the full synthetic V-twin may be able to hold it's viscosity better in the high heat. I'm not saying my engine is perfect either. It may have higher clearences than it should, but i'm not about to tear it down either.

I'm currently looking into trying a different oil, possibly the Amsoil Dominator 15-50. Is it better than the V-twin? Should I try a different filter while i'm at it? I'm coming up on 22hrs and the oil is looking like a nicely nixed cap'n coke. I know, i need to be able to keep the oil temps down better. I'm pretty sure after 5 years of completing the winterization and seeing the drain ports on the manifolds getting blocked off with bigger sand particles from the river, that the oil cooler probably isn't working at it's highest effeciency either. I'm either going to replace it with a new oe cooler for next season, or ask Mr. Cool to build me a Merc clone but with an extra inch or two longer.

Thoughts? Thanks for reading the millionth oil temp thread.

both oils yoiu have mentioned are good oils with zinc in the mix,a new larger cooler can,t hurt anything,220 is good on a hard run,after 230,i start wondering why.

the v twin mobile one is not a full synthetic oil..i talked to the guy that blends my oil for me and he said m! is about 38% synthetic...he went on and told me that liqui moly is 100% synthetic..im going to have the local napa get me some 10w60 and im going to check it out and see how it works..i still think the m1-302 is a good filter..

http://www.liqui-moly.de/liquimoly/p...oiladb=web.nsf

Btw, just thought I would add that i'm picking up the oil temp up at the remote oil filter mount.

-RW

A 10w60 should show higher oil pressure than a 20w50 because at higher temps, it is a more viscus fluid.

230 is not hot for oil. It is graded at 210.