Ok, flame on, I went with this. Valvoline VR1 racing/high zinc 20-50, I think it’s dino not syn but I liked that it had higher zinc. It fired right up and ran smooth w/ ~60 psi oil. I took it out on the freeway after warmup and ran it hard in top gear to build up heat, then would downshift into 4th and hold it to 5k rpm. Ran like a champ, now that it has heat I took the off-ramp and let it fall to idle in town ~15 psi this is where it would usually rattle like diesel on the valvetrain and show barely single digits on pressure. nothing, no noise at all. Super quiet. I hope this keeps up when it gets above 80° here and I pull my boat with it.
Very promising so far. I’ll run this for 5k or so then do synthetic version of the same oil.
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