cobra vs gt gas mileage

i have no clue, but if someone wants to reference, ive clocked my car with 2.83 rear gears while beating the crap out of my car for the last two tanks of gas (problems with the girl means ive been angry and late often, lol) and i got 18.9 and 19.6 MPG, all city miles... and i have clocked 24.7 and 25.8 highway MPG, so either way, these GT's arent too bad i guess in pretty much stock form...
 
It is possible that the cobra would get better gas mileage than the gt. Mostly due to slightly better flowing intake and heads not to mention roller rockers. It makes for a slightly more effecient combo. I seriously doubt it would be by much though. I've never checked mine because I had a problem with my car running way to rich. Since I've replaced the O2 sensors and done some work so I'll probly check it soon. The stock window sticker said 17 city 25 highway.

The transmission difference is minor and the gear ratios are the same so that should have no affect on gas mileage.
 
All the gear ratio's are the same on the gt's and cobra's. Both have 3.35 1st gear. The only difference's are a phosphate coating on the gears and a roller pocket bearing on the cobra's. It allows them to have a 310ft lb torque rating. The 2.95 1st gear T5 handle's 335ft lb of torque and I think it's only available aftermarket but I'm not totally sure about that.
 
i see about 17mpg on average with my GT and 3.08's doing about 50/50 highway/town driving. Aside from the cobra's 24lb injectors, I cant see how the small differences between a gt and cobra engine could account for any measurable increase or decrease in mpg.
 
what's up with gas mileage??? why you buy mustang if you worry about gas? i have h/c/i and 4:10 and almost all bolt-on goodies so my gas mileage went out the window long long time ago. even 2007 v6 mustang gas mileage sucks, i know because i have one :)