I would think as the run or dyno pull progresses, the heat generated by friction at rod and main bearings, for starters, would heat up a lot right before it leaves the bearings, then mixes with the oil in the pan, heating that up some? So a straight weight 50 would change the most, a 0w20 the least. Sound logical?
That seems to make sense to me.

Last edited by gregsdart; 02/02/23 09:50 PM.
8..603 156 mph best, 2905 lbs 549, indy 572-13, alky