Marvel is mainly a 5W light oil with a little naphtha, some phosphorus, and a dash of wintergreen for the smell. Bitron is 100% oil of snake. Hell, the guy who sells it here didn't even know Supras don't have oil warning lights and he owns one. Lucas? Look here:
http://tinyurl.com/2y7fj
Don't fall for additive marketing BS and don't put anything in your crankcase but good oil that huge companies with millions of dollars in R&D and PHD chemists worked years to develop and constantly improve. If any of that crap worked don't you think they'd already be using it? Or the automakers would?
I know you're in a hurry to get your car going but you'd better take your time to check it out. Every Supra I've ever looked at wasn't running right even though the owner thought it was fine.