Only the 08 Bullitts have the adaptive spark, the 09 Mustangs are supposed to have it.

 

actually it burns slower...not better slower.

 

I ran 91 for a while when I was draining the 87 out of my car for a new tune. I didn't notice any difference for better or for worse.

 

That statement could not be any more wrong. Since you're only doing a couple tanks, its no biggie. Running 93 in an engine tuned for 87 will actually result in small particulates not fully combusting. The octane rating relates to the point at which the fuel will combust. When you run 87 in a car tuned for 93, you get knock (pre-detonation) which is when the fuel "explodes" before it is supposed to. Running a higher octane than recommended will not exactly"clean out your tank"... You won't notice any negative performance related to running higher octanes, other than the performance of your wallet. There may be a placebo effect to that as well.

 

Shell's 93 has 5 times the detergents as federally mandated fuel. Clean cumbstion chamber is something to crow about, but no power gains if you are stock.

 

i have had the car since jan 2 2007 and it only has 1900 miles on it. figured this tank might last me till middle of april. i will know by then what i want to do!! supercharger or not!!!

 

Yeah the additives are what keeps the tank clean.. not the octane rating... good point.[sm=bounceybounce.gif]