Q: I fill up my Audi A4 3.0 with the minimum 91 Octane that is asking for. But my question is if I fill up the tank with 91 octane and add those octane boosters, is there any performance difference? is there a long term effect that will damage my car? If there is no problem, what type of brand do you suggest? Thanks for the help.
A: The dude above me is correct. The higher octane will not benefit most engines. However, being that your 3.0 is German... you may benefit. I know on the inside of my gas compartment lid... it recommends a higher grade fuel. I think it says 96 octane. I drive a b6S4 avant. There are guys on the Audizine forums talking about 100+ octane fuel but they also talk about chip settings and other mods. I would recommend gettin some advice from these dudes first before you do anything thats gonna ruin your engine.