i just bought a 86 n/a rx-7 and it has the emmissions removed. basically anything that could be removed has been....and the kid i bought it from said to mix 6 oz. of marine oil in the gas everytime i fill up. and i was wondering if someone could explain why and what oils best to use.

 

first it's "concerning" for future reference.

second, the oil addage means that he also took out the oil metering pump (injects oil to lubricate apex seals) - the advantage to this is that 2 stroke oil tends to burn more cleanly and instead of a mechanical device failing the driver's memory fails.

Any TCW-3 2 stroke oil should be fine for your use. You may want to use more than 6oz (maybe up to 1 ounce per gallon).

You can research more by searching for "premixing" or "premix" as this is what this is called because you pre mix the oil with the gasoline instead of having the stock system do it for you.