wat kind of fuel can i put in to my 300ex to get better performance??

 

What does you owner's manual recommend???? Is it stock compression???

There is this myth that you can get more performance out of higher octane fuel. If you are getting detonation or high compression, then run higher octane for sure, but otherwise you can actually get a decrease in performance with to high an octane....

What I do is run what the owner's manual suggests, but I add a little Klotz Octane Booster. Not enought that I am getting a huge increase in octane, but enough that I am hedging my bets against any possible detonation (fuel octane will decrease during storage!). Better yet, the Klotz contains an ester synthetic lube for the top end (!!!), and a fuel preservative.