So I have a 2014 v6 with borla Axel backs, an xpipe, shorty headers and a air raid modular intake with the stock airbox. I recently got a 87 tune from auto race mafia and my mpg in the city is like 16.3. Used to be higher before the tune. Also, the car takes awhile to shift out of first in neighborhoods, so I'm cruising around at high rpms. Does this sound normal? It's my first time running a tune.
thanks

 

Most of us v6'ers run MPT or Bama tunes. My Evolution Performance tune made by Jon Lund gets around 18 MPG on the roads I drive. My MPT tune gets me around 21 MPG on the same roads. My tunes do hold the gears a little longer and shift hard and fast, so I guess it's normal. I've been running tunes in my 2011 Mustang since August 2010 and the automatic transmission has had zero problems, but I only have a little over 35,000 miles

 

I think you need to talk with the tuner about the issues you are experiencing, and they should be able to understand what you are saying and adjust the tune accordingly. The shifting might be intentional; holding lower gear longer for better performance, and should be controllable/adjustable. Holding lower gear could also reduce the MPG

 

I just requested an updated tune. My car is a daily driver, so I can sacrifice some power for gas mileage.

Also I'm at 80,000 miles and bought the car at 60,000 but I'm pretty sure the spark plugs and o2 sensors haven't been replaced at all. That could be another culprit for the low mpg. The car cold starts at 1.5k which is pretty high too, but that could just be the tune.

 

yes I believe the cold start-up idle can be set in the tune

pretty sure spark plugs and O2 sensors are good for over 100K miles so that should not be an issue, check owner's manual maintenance schedule

 

I am getting under 20 MPG on mine with my BAMA Performance tune in, I have a 89 Tune I run on long trips that is more Economical that I have gotten 30+ on trips to Florida. My F150 Gets 18 on a good day with a tailwind and downhill.

 

Please expand on how you get 30+ on trips please. New 2013 3.7 owner here. I want that 30+ and do not want to mod and never see that.

 

My Mustang without a tune going to Massachusetts was getting 34.3 MPG for the average for the whole trip and it is a Manual that is supposed to be 29 highway. Most of the miles going to Mass are in states with 65 Mile per hour speed limits, I am a Truck driver and I normally do not speed due to my license.
I have a 89 tune from BAMA that when I put it in going to see my Mom in Ft. Myers still gets over 30MPG. You have to remember when the Mustang came out it was a 305HP car that got over 30 MPG with the 2.73 gears that I do not have, mine is a performance package with 3.31 gears. Florida is mostly 70 miles an hour + so lower MPG.

 

About the mileage -- I used to get 27 MPG in my 2010 GT on my mostly-highway commute, driving nice and easy. All the usual tricks apply -- keep the RPM's down, coast when you can, avoid using the brakes if possible (brakes are energy dumps; once you get the car rolling, you want to let it keep rolling if you can), and keep the speed down. Generally the best mileage will be in the top transmission gear at the slowest speed you can maintain in that gear, without bogging the engine. I used to do things like coast in neutral, if there was an opportunity like a long down hill on the highway.

Mods generally will not improve mileage; though there are a few that might help a little. Shorter gears and wider tires usually will hurt your mileage.

 

When I put the 305/50 20's on my truck I lost 1-1.5 MPG and when you see 16 on a really good day but with a mix of 14 MPG on average that is a bit LOL. The Mustang is getting 21-22 right now around town and with the 295's on the back 27-28 on the open road.

 

So without a tune and any mods to see the 34mpg?I have a 2013 manual as well and have BBK shorty's on the way. In order to see that mpg should I install them? I will be primarily driving 70mph plus on highways thanks for the quick response..

 

The shorties actually help since it will give you more low to mid range torque and allow you to stay in a higher gear. I do not remember any noticeable hit on the mileage when I put mine on.