My MPGs went Bye bye

[s1975oh]

I remember the days when i got a nice solid 27-30 mpgs on the highway when i had 3.31s, JLT intake, BAMA tune and pypes bomb axelbacks.

Now I have

JLT CAI, BOSS intake, OR X, resonator delete, GT 500 AB, 3.73s, Gt500 wheels with 285 35 19's all the way around, I run a MPT 93 performance tune. I struggle to get 20 on the highway now. I don't daily my car but its annoying as I like to take it on long trips, sometimes I swear i turn on the car and the gas gauge moves. I was aware that the 3.73s would decrease highway mpgs but somehow I feel there is more to it. Is this normal?

 

[burke985]

Well take all that stuff off and put the other stuff back on

 

[s1975oh]

Nah lol, Im not under forced induction or anything so I don't see why my fuel economy at cruise should be that low, should still be getting over 20 no?

 

[FIVEHOE]

depends on how much of a lead foot you have lol. That and I would manually record miles/mpg. Sometimes the tachometer can be off

 

[burke985]

Probably your new tune and the 3.73's doing most of the mpg loss. I still get 23-24 if I play real nice with the blower on the interstate

 

[five.slow]

wow i was getting 29-30 on the highway with a paxton and 3.31s. difference in 3.31s and 3.73s on the highway are not big enough to kill milage. i had 3.73s for a while too and still got around 30 on the highway.

 

[USNjocson]

I start in 2nd gear, shift at 1900 and roll my car in neutral to save gas in my 3.73

 

[five.slow]

i just drove like a old lady. now its easier since the car does the shifts for me lol.

 

[burke985]

wow i was getting 29-30 on the highway with a paxton and 3.31s.

well you were doing better than most , hell stock they don't even get that good of mileage :shrug:...did you drive it over 60

 

[nsty4vlve]

I get 24 with my Paxton on 91 and 3.55s. Part of the problem is winter fuel sucks!

 

[OMG_5.0]

I gotta say that I didn't buy a Mustang to save on gas

 

[RFM50]

It has to be a combo of the tune and gears. I had a dyno tune done that i couldn't get better than 22 on the highway. That tune put down 680. I now have a jlt remote tune that pulls much harder and i can get 26-28 on the highway. Your not going to get 26 with those gears but should be able to get 22-23. Consider a different tuner.

 

[Quesplosive]

I get 28 mpg now on the highway with the turbos, but before them it was about the same. You should be getting a bit more. I had bama, vmp, and now bbr tunes.

 

[john11gt]

I average about 20-21 mpg with the 3.73 gears. Starting in 2nd, shifting at 3k and cruising at 75-80 on the highway. I got 25ish on my way to and from northern Wisconsin on the highway. I dont get how some people are always getting high 20 mpgs, they must be never getting into the throttle.

 

[D.T.R]

I get 28 mpg now on the highway with the turbos, but before them it was about the same. You should be getting a bit more. I had bama, vmp, and now bbr tunes.

haha that's pretty awesome.

 

[12mustang5.0]

If you really want good mpgs sell your mustang and buy a focus
My stock car gets 26 in hwy with 331s but if it would of been 20 mpg i would of been happy just because once i take it to redline it makes me smile.. Why worry about mpg in a car that isnt ment to be a gas saver

 

[dead man walkin]

I'm with john.. that's what I get 18-19 city and 20-23 highway.. but I knew this going in.. I also knew it was going to be 93 octane so ehhh. I know revving the engine isn't good for mpg either but I loooooove that sweet sweet rumble and snarl and pop my exhaust gives. It makes dogs growl, children cover their ears. 3.73 ftw

 

[Tyler72]

I get about 15 around town, best I have ever gotten on the highway was 23.

Its a mustang, dont worry about mpg.

 

[Aaron@JPCRacing]

This was on the way down to Myrtle beach this year in our racecar -

Not bad for a 7 second car.

 

[Rct851]

I never display anything but track apps. If anything about 12mpgs means I had a great time lol