I stick with the Mobil 0w40. I live in FL where its routinely 100 degrees + 100 % humidity. Intake temps up around 110- 120 and car barely uses any oil in 5k intervals. I think either or you are fine. At this point its preference.

 

For what it's worth, Manthey in Europe runs Castrol TWS 10W60 in all their track duty Mezgers. I've always been wanting to try this oil during the summer track season.

 

I've run M1 0w40, 5w40TDT, and 5w50. All are fine for the street but I would not run 0w40 at the track. In hot conditions it thins down to the point where I've seen cars get a low oil pressure light at idle after coming off a 30 min track session with hot oil temps. I've seen this booth in TTs and GT3s. I've had great success with 5w50 over the last 100+ track hours. Just like anything, use what gives you the warm and fuzzy...

 

I'm sure they're motors may be built? And may have diff clearances? I wouldn't put 10 60 in this car. And it's expensive too.

 

My understanding is on it's on stock motors. Go figure...

 

Interesting. It's a good oil but like syrup.

 

I am still running Rotella T6 5w40 in mine and like it. I have heard great things about castrol.

 

i've run both castrol edge 5/40 as well as 5/50 and even 50/50 blends of them and car just purrs esp at startup in hi ambient summer temps. hardly scientific but, whatever. only reason I'm running m1 5/50 now ( and have been ) is the deal on it from amazon was too good to pass up and my decklid has an m1 sticker

 

As am I for the past 5 years. I've done oil analysis with each change and the notes from Blackstone have always come back extremely positive.