I have been running GC in my twin turbo Audi S4 for the past 4 years. Oil did well during the street and track use as confirmed by my UOA results.
This weekend I replaced GC with Redline 5w-30 to get a bit more safety cushion with high oil temperatures car sees during the track duty (275-280F range).
Car runs smooth(er) and I also noticed faster turbo spool up then I ever had with GC
Here are their respective specs:
GC RL
vis @ 100C 12.1 10.6
HTHS 3.6 3.8
I guess Redline just has lower coefficient of friction?
This weekend I replaced GC with Redline 5w-30 to get a bit more safety cushion with high oil temperatures car sees during the track duty (275-280F range).
Car runs smooth(er) and I also noticed faster turbo spool up then I ever had with GC
Here are their respective specs:
GC RL
vis @ 100C 12.1 10.6
HTHS 3.6 3.8
I guess Redline just has lower coefficient of friction?