Robert Linton

For track use, would you use Kendall GT-1 20W50, a mineral based oil, or Mobil 1 15W50, a synthetic oil, or Castrol RS 10W60, a synthetic oil, and why? And for street use which one?

Bill Gregory

I use Mobil 1 15W50 for the track. I don't use a mineral oil-based motor oil for the track, as I believe Mobil 1, and other similar synthetics, offer advantages in strength and resistance to break down, particularly at the higher running temperatures and stresses of the track environment. Availability is also a consideration, ie, Mobil 1 is readily available. On the street, I use the same oil for Spring-fall usage.

Robert Linton

Thank you. I wonder, however, assuming you change oil after every track event, if the Kendall might not provide better protection - particularly for the camshafts. In street driving, though, I would definitely opt for the synthetic.

RSAErick

Go with the best. Amsoil 20W-50 Racing oil. I wouldn't put anything less into a car that will see a track. My opinion, of course.
Erick

Bill Gregory

[quote]<strong>assuming you change oil after every track event</strong><hr></blockquote>
I don't change the oil after each event, as it's a daily driver which also sees track time (or is it the other way around ). If I were racing and rebuilding the engine every 30-40 hours, that would be a different scenerio to consider oil brand/type.

Anatol

My mechanic here in Switzerland prepares quite a large number of RS for racing. He says that Castrol RS is perfectly suited for tracking normal aspirated cars.

According to him Mobil 1 or better is only needed for turbo cars like the 964 Cup car that a client had him convert to 993 GT2 with 650 bhp.

But choosing oil seems to be as much a religous act as choosing tyres...

Anatol
1991 C2