I have a 2002 9.9 johnson 4 stroke..what octane gas should i use?

-Regular Unleaded in 87 octane is all you'll ever need. You may want to add Sta-Bil additive to keep the gas fresh and the fuel system free from varnish.you will be just fine using regular 87 octane fuel. i have done it for years. high test is only needed for higher compression motors and performance applications.
Most engines run on REGULAR UNLEADED 87octane gasoline.



On most engines, there should be a sticker to tell you what octane to use as well.