Ran 5W-30 royal purple for 5 years in my cobra. Had 600hp on a stock bottom end, and I beat the piss out of that thing. When I went to get it smogged for the first time, the numbers were better than most new hondas. The engine was immaculate internally as well. Other oils I'd recommend would be redline, valvoline SYN and Quaker State Q high rpm. All have very good additive spectrums and have seen how well they work first hand. I dont get the hype about Mobil 1. I used to drain that crap out of my cobra (the 2 times I tried it) after 4000 miles and it looked like tar. I would drain the RP after 8-10,000 miles and it would still look new. I also use Mobil soluble oil in my CNC's for cutting lubricant, and that crap is by far the worst garbage soluble Ive used. It goes rotten with bacteria in a month, is mixed terribly and decomposes and separates from the water VERY fast. I use Global West lubricants now and couldnt be happier. After 6 months of milling, the oil is still good and doesnt smell like rotting flesh. Im not very happy with the Mobil name. Just cause they're huge and the oil testing which they fund shows good numbers, that doesnt mean anything.
