I have 11.5:1 compression and I've been using AV gas 100 octane in it for years. Last week someone told me that it has air mixed into the fuel for high altitude motors as in airplanes and that this mixture is not so good for car engines. Apperently it leans them out and even causes predetination. He suggested using 94 octane with 108 octane booster mixed in it. Is there any merit to this?