Mudflap

Oddly enough, I had about 4 Chevron stations on my ban list for my WRX. IMO it all depends on who they buy from locally...

2oo5stang

Your car will be fine with the higher octane fuel tune. even in the summer on 93 octane, and ifit pings, you can call the tuner that you bought from and let him know or you can always go into your tuner and take some timing out of it and it's fixed. Also brents or bama's tune is bascially what they think is best for your car with your mods but all cars are different,but great for a starter tune. Andone might like so much timing and another might ping alittle under load, but it's a easy fix. Like mentioned the dyno tune is best, they can safely squeeze all the HP out and have a safe A/F ratio which is key to a fat and happy mustang. 93 isn't hurting your car no more than 87, maybe your wallet but that's all, your not increasing the compression or adding boost to it, just advanced timing. When you get a tuner, try them all out to see which one is best for you, i would do each octane tune for atleast a week and then jump to the next one, to get a better feel or see if their is a difference between them.
Also about the octane boosters, they did a test on them a few years a go and alot of them, give 0-1 octane point boost at mostexcept Maximum 104 octane boost, it gave either 2-3 octane pointboost. So if your not buying that brand, your mostly wasting money if it's about adding octane points.

white07

my bad i just thought about t and i meant to say exxon.

while we are on the subject isnt there some kind of problem with the new GTs at the pumps? the pump just cuts off? How do you make it work?

Daniel60

Everybody talks of gas but I believe it's more the gas station you go to. I hear you never get gas from a pump when a gas truck is loading new fuel in the tanks because chances are you will get the trash from the bottom of the tank. Also I have spoke with a gas truck driverand he saids there isn't any difference that he refuels gas stations not a particular one.

Warlok

I dont know what some folks are even talking about here. There is not one reason in the world to wonder or worry weather its "safe" to run Brenspeeds 93 octane tune. Of course its safe. I have been running it since my 07 GT had 1.200 miles on it. It has over 13.000 now and has allways ran the 93 tune but for the first time when I ran the 87 tune to get the 87 octane out of my car before switching. I switched the tune right at the pump to 93 octane.

93 octane gas is more efficiant and burns more compleatly, hence better mileage. I average 21 mpg in the city and im never babying it. Highway mileage runs around 25 to 26 at 70mph and 23 mpg at 80 mph. I live in Texas and premium is $2.85 a gallon here where I live. Just my opinion, buts its been working fine for me.

Sprzout

How true...I found out that most of the gas here in San Diego comes from one location that's piped in, and depending on what brand of gas it is, they just add additives there and truck it over to your local gas station. Basically, the Costco here in town gets pretty much the same gas as the Chevron station down the street that's charging 20 cents a gallon more.

Anyway, back on the topic of the tune:

I'll probably only ever run 87 or 91 octane tunes in my car. Why? Because California only has 87, 89, and 91 octane. And most gas stations that I go to, they only carry 87 or 91 octane. I'll stick with the 87 tune when the time comes for me to do the upgrade, and I'll probably go with Brenspeed and a C&L Intake. I COULD always take it to get it dyno'd, but the only dyno shop in the area that does an SCT tune is freakin' outrageous. All of the others use Diablosport tuners, which doesn't seem to be too popular...

Foose12

+1. I'm in stationed here in DC and they have 93 octane everywhere. I went with 91 octane tunes in case I go somewhere that doesn't have 93

RomanPacific

How much of a difference does the 87 tune make over stock and compared to a 91 or 93?

miltoneagle

I just ordered a C&L and brenspeed tune. I was just wondering what the rules were when it comes to switching back and forth between octanetunes.

If im running 93 octane with a 93 tune then do i just switch the tuner to 87 and then put in87 octane? and the other way around?

howarmat

Never run a lower octane gas than what is loaded from the tuner. You can do damage since there are adjustments made for the higher octance to gain the higher HP. (timing spark and whatnot). You can run a lower tune with higher level gas but you wont be getting as much out of the gas as you would with the proper tune. I have always run93 Oct with the 93 tune. There is no good reason to switch tunes around. Get the tune that matches the octane you have available. If you have only 92 available then ask for a 92 tune. If 91 is the best gas you can get load that tune and leave it!