I use AMSOIL 20W-50 (fully synthetic) in my race engines. If I were concerned about high heat and wear I would also use it in my 944. But since I'm not, I don't. For 'Herbie', I just use conventional petroleum based oil of 10W-30 grade. Usually, it is Mobil or Shell - which ever I can get for about $1 per quart. I change oil and filter religiously at 3000 mile intervals.

Frequent changes with a quality oil is the key. Naturally, synthetics are better. One of the nice things about synthetics is that you can leave it in for many more miles than conventional oil. Thus offsetting some of that initial cost that makes them seem so expensive.

 

I love these posts- I ALWAYS know the answer.

Mobil 1 15w50.. exclusively for almost 6 years, lotsa miles- all road and weather conditions.

 

Castrol TSW Motorsport

 

Mobil1 5W-50. Only available in Europe, I think.

 

I use Valvoline Racing 20w50, i find it much better then Mobil1.

 

Lots of Mobil 1 users, 15-50 as I use in my 86 na since my rebuild.

Opinion time!

How often do you change your Mobil 1 in your P-car?

I may have barely hit 3k miles and am approaching the 1 year mark. I have the last DE of the season, Mid Ohio, at the end of October. Do I change now or wait till after the last session?

And yes, I run the heck out of my car and it doesn't burn a measurable drop!

 

Ampoil Max100 10w/60 synthetic

 

Redline 20W50 only

on track oil pressure with Mobil 1 15W50 is scary, IMHO