Street driven vehicle...just wondering how much heat is 'generally' generated by working the oil...20/30 degree's?
It definitely depends on the engine, but figure 20-30 degrees as being being pretty common.
The reason oils formulas need a high NOACK is that the oil in the piston ring pack is often over 400*F.
There isn't a lot of circulation in that area. some engines have under-piston oil squirters. They should about be mandatory for any vehicle that does a lot of towing.