winter track events and oil

#1

Not that I am asking anyone to give up any secret performance tips (maybe I am), but my gut tells me to run a lower vicosity oil (e.g., 10w 30) rather than the 20w 50 recommended by the M20 owners guide. We ran our 240z year round on mobil 1 10w30 with great results, but it was a built racing motor, not a stock engine. Any thoughts?

Thanks,
Ed

#2

I switched to 10W40 in the winter on my old daily driver because I was seeing cavitation during morning drives (little bubbles suspended in the oil) using 20W50.

#3

Ed:

I’ve used the 20/50 in all weather and it hasn’t been a problem. Your assumption makes sense though…

Carter