Newb here) i got a 2010 GT not to long ago and I was reading the owners manual about putting 89 (I think) or higher. So ever since I got the car I have been using super. So I was wondering what are you guys using?

 

I use 91 which is the highest in my area. You will get about 10+ HP using 91+ over 89.

 

I use 87 octane unless I want the "zing" of 10 extra lb-ft of torque by using 91 octane.

 

i decided to put 87 for the winter since the extra HP and torque are pretty useless in snow.

 

I use only BP Ultimate (93) in my car.

Unless its really hot at the track where I mix the 93 with 100 race gas to combat knocking

75% 93 oct
25% 100 oct

 

Since you have a 2010 and thus the 4.6L v8 you don't need the higher octane fuel. I do believe that all 2010's have the adaptive programming the previous bullit's had, so you're not damaging anything by running the higher octane. It's certainly not necessary unless you are hearing ping.

If the owners manual states to run 89, that's what I would run. Unless it's tuned for higher octane you're just wasting money.

 

All my tunes are for 93, only 93 for my baby

 

93 only here.

 

Was using 93 but now back to 87 since gas prices cost an arm and a leg.

 

Only a few stations have 91 here so its 93 for me.

 

I think you have things a bit mixed up here. The adaptative tuning means that using higher octane does give you more power so you're not wasting money like you would on a car tuned for 87 w/o adaptative tuning.

Also, you wouldn't damage your engine by running higher octane than recommended but you could by running lower than recommended.

 

Marathon 93 is all mine has seen.

 

Adaptive tuning is not limitless. It advances the timing as much as possible to take advantage of the knock resistance of higher octane fuel but timing can only be advanced so far before it becomes counter-productive. The horsepower rating on the 5.0 is using 91 octane premium fuel. There is no indication that using even higher octane (93 or more) further improves performance at all (without a tune of course). Similarly, the V6 is rated 305 horsepower using 87 octane regular fuel. There is no indication yet that using higher octane in a V6 does anything but waste money... it's possible but we don't know.

 

Running 91 because of my 91 tune. =]

I live in CA, don't know what this "93" stuff is... =P

 

That's true, but the tuning differences between the 4.6L motor and the 5.0L motor are vast.

The 4,6L motor was designed around 87 octane fuel. While the adaptive computing can take advantage of fuel grades to an extent, it can only go so far.

There's a reason the 5.0L owners manual does not specify an octane rating, while the 2010 does. In the progression of technology things get better. the Bullit and 2010 2.6L mustangs represented a first start for this tuning process in ford vehicles.

Unless the car has a tune specifically for a higher octane, members with the 4,6L motor should follow the owners guide for octane rating.

In regards to engine damage, using an octane that is too high for an engine can result in an incomplete burn mixture which can create carbon deposits on the top of the pistons and bottom of the valves. These deposits over time can create hot spots in the combustion chamber that with the use of the manufacturer specified octane my cause ping and detonation.

Always run your vehicle for it's intended octane.

 

Shell 93

 

Actually, the 2010/11 owner's manual does specify octane rating. For the V6 it says 87 octane. For the V8 it says 87 octane but that using 91 octane will give better performance (you get 400 HP using 87 octane and 412 HP using 91 octane).

 

I use 87 in my 2010 GT for normal daily driving (my 'stang is my DD)

I have tried 93 but couldn't really tell the difference in normal street driving. The 2010 4.6 engine supposedly makes the same max HP regardless of octane (87 minimum) and makes more torque in the lower RPM's on higher octane (probably because it advances the timing). If I was going to the track I would fill up with 93 but for every day driving I think it is a waste of money.

Brand of fuel is a different question -- there are "top tier" fuels that supposedly have higher detergent additive levels that are supposed to be better for the engine . . . I put in a tankfull of "top tier" every half-dozen tanks (give or take a few), and use whatever is cheapest the rest of the time.

 

wow, I guess I finally found the one place that is worse than Massachusetts . . . we can't buy gas without ethanol in it, but at least we can get 93 octane

 

I used 87 or 93 where Iam at, in tri-state if in Cinny, OH area I used 93 because it's $3.15 at Shell and around home 87 at $3.09 gallon.