I was using VR1 10w30 non synthetic without issues!! My engine is fine and no problem. Right now, I will use VR1 20w50 because 10w30 is over and only can get 20w50 but I think is fine!

 

I use vr1 20w50 non synthetic in my X, no issues what so ever. I tried the vr1 synthetic 20w50 and I get a bit of white smoke after wot. Switched back to the non synthetic 20w50 and the smoking issues went away. Lol

 

Just switched over to VR1 Comventional after my tuner recommended it. They advise all new builds to use this oil as well as old cars. Even Buschur racing recommends the Conventional Vr1. After 1k I am going to run an oil analysis and see how it's holding.