Everybody has their favorite fuel so use a good brand. Look for 20-30% Nitro and 20% or as close as you can get to it in oil content. I push my boats a little harder than most for this size motor and have run 45-50% Nitro but I don't advise this for everybody. You start blowing a lot of plugs and the needle gets more fickle with high Nitro plus it cuts the life of the motor down.