We've been using Mobil 1 0w50 racing
oil in our engines for many years....and my colleagues at Newman/Haas have been been using it as well......
We run motors harder then anybody on this board....and in many different engine types....(Ford,Chevy, Indy car type)......
By the way....it has a ZDDP level in the 1800's ppm.....great
oil especially when you only start them....run them .....then park them for a while....