I'm doing a turbo in my 95 cobra....dumb question but I been running NAPA 5w30 synthetic but I'm gonna start using royal purple next oil change with the turbo...just wondering if 5w30 is ok...don't know if turbo would change anything

 

5w30 should be fine. If you feel uncomfortable then you could run a bit thicker like 10w40. But honestly I think full synthetic 5w30 should be fine.

I would do some searching on google what the supra guys run, that should tell you.

 

Most of my import friends run a 5w30 if I remember correct. My buddy swapped an FP Green turbo on and now he needs 10w30 or 10w40, I don't remember which.

 

Just a thought but if you havent rebuilt your motor with higher performance internals what's the point of switching over to a different but still synthetic oil