Does the Premium Gas for $0.10 more make a difference? If so what does it do, and will it improve MPG? I've searched google and found not much information about it. Also will it improve performance (I'm all stock except a K&N Air Filter)?

[Sorry for so many questions! It's never ending with me! :P]

 

Premium gas won't make any difference at all if your car is STOCK and is designed to run on regular octane.

Cars like the Shelby's & Cobras that are blown require premium gas, and you shouldn't go cheap on them & run regular instead. That'll damage the engine

 

With the assumption we're talking about a stock car capable of running low-grade fuel.

Higher octane fuel gives you the capability to alter the engine to achieve more power. Higher octane fuel alone will not increase power, that comes from a change in the tuning on a car (such as with a tuner). Higher octane fuels are most commonly associated with timing changes, but can play into forced induction or even engine compression changes.

 

the best thing to do is run premium in your car one reason is it burns cleaner and you will get better gas milage, another thing it will help your engine to last longer, and you well see a little more differance in performace, but not much unless you have aftermarket stuff. but if you have a v8 or alot of mods done to a v6 i would run premium in those all the time. in my car since i have the v6 its fine cuz i dont plan on doing anything to it but drive it.

 

Only run premium in your car if you get a tune for it(from a SCT/Diablo tuner, Dyno tune, or chip). If you don't get a tune for it, you are just wasting your money.

Everything else in the posts stated above perfectly explain it.

 

Filling with Plus or Premium helps higher mileage cars(such as mine) as well.
I have 90k on the clock and filling with Plus over Regular gives me a reasonable 1-2 MPG boost.

 

So it WONT help at all with better mpg?

 

If i try using anything lower than premium in my 93 there is sputtering and usually some pinging. My timing is 12-13 (stock is 10) and other than the exhaust and gears, im pretty much stock. Switched back to premium and she ran fine again.

If the only mod you have right now is a K&N and you keep your 'stang properly and regularly maintained, you should be ok running 87. Bump the timing or start digging into the motor tho and id start using the higher stuff.

 

http://ezinearticles.com/?Save-Money...ctor&id=500768

 

Actually, without a tune, higher octane fuel may hurt performance. Higher octane fuel has a higher resistance to "burning", which can lead to less power as the engine isn't running as efficient.

High or low miles has absolutely nothing to do with whether higher octane fuels are worth it, or whether they "help".

Higher than stock timing will require a higher octane rating, which is exactly what you experienced. I always had my Fox at 14 degrees with 93 octane, before I tore it down and started a rebuild.