i have a 72 buick gs stage 2,,455/30 over,,flat tappet motor,,when i got it the guy told me he runs rotella t oil in it because it a flat tappet motor,,should i stick with that or can i change to royal purple,,roetlla t has all the good stuff for a f. tappet motor,,,does royal purple??
Yes. You can change to royal purple.
Man that engine is a torque monter, I had a 1970 Riviera GS with the same 455-425-HP engine and couldn't keep tires on the rear. There is no need to stay with Rotella after the break-in period if done properly. All oil manufacturers by Federal mandate has reduced or removed the zinc additives your camshaft depends on from their oil. Switching to Royal Purple is a no lose proposition, be sure to buy their oil additive and add it every other oil change and live happily ever after. P.S. always use a high quality oil filter, I use K&N filterchargers or Fram filters in every car I have owned.