I have tried a number of oils in my car, and can only reccomend what I have used.
The best stuff I have noticed is Redline 10w 40 which I use in the winter, will go to gloopier redline variant in Summer. It warms up quicker than anything else I have used and gets no hotter than 80c. It holds Oil pressure better than anything else as well at 6 tweakers.
I had the opportunity to speak to there head UK biochemist who explained about the base stocks etc, and how they and Motul only use the best quality base stocks.
I would also highly reccomend putting their heavy duty shockproof opil in your gearbox, it is incredible the differnce it makes.
My R34 had Halvoline in it from MM but in now having Motul engine oil instead.
I'll let you know of difference, if indeed any, when I get my car back!I know in my R33 once I put Motul in the oil pressure did go up and the engine did sound slightly quiter!What was in there before I know not !
I did once put Mobil 1 in but that was too thin and was taken out very quickly.
I don't think one can go far wrong with an engine oil as long as it is from a reputable manufacturer and the right viscocity.
The other factor is oil changes which I do personally every 2 to 3 thousand miles.This I think is of paramount importance especially if you track/drive the car hard!
SJD. heavy duty shock proof gearbox oil?I thought it was very important to put the right type of oil in a gearbox. Thanx.