Extreme Oil Question

This is not for my car but for my atv, I know sarge is a oil nut as are some of you dragsters. I got a 14:1 compression engine. Shaved head, ported and polished. Four stroke engine. This thing is strung at it's limits for racing. I was told by the racing team that assembled my engine for me that they rebuild theirs after every race for Honda, but said I should be able to get about 15-20 hours before a rebuild is needed. Anyways, the engine oil capacity on this thing is a joke, I thought my manual was wrong, not even a whole quart. I want the best oil money can buy and the company reccommended me to use Mobil 1 SuperSyn 15w50EP. I think they might get paid to say that though...

That's a weight I've never heard of, let alone heard of putting in a car. That sounds like gear oil or something. Am I going to be better off just going 5w-30 royal purple or amsoil? Also for some reason, on my model year they decided to remove the oil cooler to save weight, so the oil in this thing is going to be put to it's limits.