"synth's are formulated for racing"
well, interesting enough I just left a guy who bought some of our 20w50 race blend. He had just replaced his heads and it turned out they had 4 bent valves.
His comments were as follows...
first thing he noticed was oil pressure dropped from 60 to 40psi..(he was running straight 50 prior to this)
engine temp dropped from 180 to 150deg's. He had to block his radiator with cardboard to get a higher temp. (this is down here in florida)
He turned out 5th out of 21. But that was with the 4 bent valves and turns out he had 1 bent push rod. He stated (and I really don't understand all of this so I might say it incorrectly) that he had 200ft lbs? of spring pressure on his valves or seats? anyway from the way he talked he expected the cam to be wiped out. He pulled the head off, pulled the lifters and saw no damange at all on either the lifters nor the cam. He runs achahol fuel and even with an intake valve stuck open, and finishing the race, he stated that the oil was still as green as when he put it in and is going to continue to run it again tonight and expects to run it atleast another time for a total of 3 nights.
He also stated he is not going back with the other oil as he knows for a fact that had it been in there the cam would have been wiped out.
This guy is a master ase mechanic at toyota as well as the other guy I usuall talk with and has a lot of background and experience in building race engines.
Anyway, thought I'd share that with you.