swaq said:
Dr Haas has forgot more about oil than I will likely ever know.
Take a look in the oil section, there's a thread on "favorite oil" with a lot of good info in it. I like German Castrol 0W-30 (Grp IV PAO)...Red Line 5W-30 (Grp V ester) is outstanding, but a bit expensive. Royal Purple 5W-30 (Grp IV PAO) is more suited to racing (frequent oil changes) and has a less robust add pack. Amsoil is actually a very good oil, especially the 2000 series 0W-30 (Grp IV PAO) , but when I tried it it made my valve train a bit noisy...your experience may differ.
Most of the remaining "synthetic" oils on the market are Grp III...not that that's bad, but I want a synthetic when I pay for a synthetic. Of these, Pennzoil Platinum stands out...they have actually taken the hydrocracking process for Grp III oils to a new level. There is little difference between it and the above oils...it is excellent.
If you motor has a bit of wear and you're showing low pressures at 3000 rpm, you might consider a 40W multigrade. There are several good 5W-40 synthetic oils out there that will flow pretty well cold.
Don't use a 15W-50...it's too thick. There are several threads in the oil section on this subject and, of course, Dr Haas' extensive article.
