gears and mpg

[Cobain03]

currently i get 14 miles to the gallon (mods in sig) and well i jsut ordered someheaders so im thinking that would put me down to about 13..well i have 2.8 gears also and was wonderin if i went with like a 3.5 ratio, how bad the mileage would suffer

 

[Max Power]

Well gears will hurt the mileage, but headers won't, neccesarily. Quite often there is an improvement with headers.

 

[Cobain03]

more power means less mpg from what i have seen...but i gues si'll trust ya

 

[NorCal66]

Well more power from better flowing heads or something which requires more fuel is one thing, but creating a less restrictive exhaust shouldn't hurt the mpg.

From what I know higher gears can actually help your gas milage if you do majority of your driving in town. It takes less to get you going from a stop apparantly, which saves gas. Take it on the freeway and it'll be a different story.

 

[69fb00GT]

more power means less mpg from what i have seen...but i gues si'll trust ya

Headers helps the engines EFFICIENCY, thereby giving a hp increase. I can't comment on mpg differences, as i feel it will most likely be negligable.

 

[Cobain03]

well 90% of my driving would be around town..most id go would be maybe 1 1/2 hours away to grandparents...

right now, when i go abuot 70 mph, you can hear the engine winding a lil bit..if i used other gears would it say, wine at 50 or wine at like 90

 

[taylor4g63]

I've got 3.55's and getting on the highway sucks. 60mph is appoaching 3000 rpm. However, around town, they are great.

 

[bnickel]

you might think about getting some 3.25 gears. depending on what you have done to the motor you might actually get better mileage on the highway even. all engines have a sweet spot where they perform best when cruising, for most street motors it is between 1500-2500 rpm, some like to wind out more than others some like just off idle better. considering the mods you've done already and the current mileage, assuming the car is properly tuned, i think you would probabaly notice a significant increase in mileage in town and possibly an increase on the highway, you may not notice any difference on the highway however and might even lose a little bit, but it would be negligible i think. i would also expect to see a very slight increase in mileage by adding headers. you might also consider running a taller rear tire as well, less revolutions of the tire means less rpm the engine has to turn as well.

 

[mdjay]

The x-factor here of course is the fact that the gears and some exhaust will may help, but your much more likely to put your foot in it 'cause it sounds and feels good. That surely won't help the mileage The best thing for milage is an efi kit and a 5 speed.

 

[2nd Mustang]

The x-factor here of course is the fact that the gears and some exhaust will may help, but your much more likely to put your foot in it 'cause it sounds and feels good. That surely won't help the mileage The best thing for milage is an efi kit and a 5 speed.

I have a 3.25 limited slip rear, headers, 302, 4 speed toploader, Holley 600 vacuum secondaries, etc. I must live by the X-factor because my mileage is about 7 mpgs around town. I do admit that my "heavy" foot is a factor . Performance is for fun........if you want economy, you need an econobox.

 

[Cobain03]

well, this car is going to be driven every day to school so i kindly dont want to go broke on gas but they way i headed,,doesnt look to good

 

[Pakrat]

What you are looking for is a complete oxy moron. If it is such a concern then you are simply driving the wrong car. You can not have your cake and eat it. Choose style or choose economy, what you want or what you need.

With my set up and the usual spirited driving I see about 8mpg on average. I recently did a test where I drove like a grandma for one full tank just to see the difference and I got about 12-13mpg instead, but I had 0 zero fun in the car too, so I am back to spirited driving again. Like a sports car, these things are not meant for the dollar concerned so decide what your priorities really are and then go from there but don't waste your time trying to make it something it's not.

 

[Ozsum2]

You will get better fuel economy out of the headers if you drive the same. It wiil create more power, with less fuel. Hence, the savings. I get 19-21 mpg on the highway with my stock 2100. Around town is 12- 15. That is with the 2.79 rear gears. And, I drive like an old lady. Damn Calif. chippy!!!

 

[Cobain03]

so harsh but so true.. maybe i should be kinda savin for like a gt fox and use the 65 as a monster,,,hmm i dunno well i guess gears will wait for a while. my headers some in tuesday! !

 

[slowboostens281]

im having rear problems

will any 8.8 ford rear fit in a 1999 gt, i rolled my axle tubing forward on the right side and now i need a new rear.

 

[Cobain03]

kinda OT but i dont have a clue

 

[mustang70]

will any 8.8 ford rear fit in a 1999 gt, i rolled my axle tubing forward on the right side and now i need a new rear.

You need to check the late model forums. But no, not all 8.8's will fit in your 99. The 99's have a slightly wider track width then the earlier years.

You can drive spiritedly and still knock down decent mileage. I averaged 13 mpg when I was driving my car. And I don't have a light foot. That was without an AOD too.

 

[mach1one]

if you don't want to go broke driving back/forth to school, buy a 500$ honda and drive it. if your gas mpg is that bad, it'll pay for itself after several months. Mine did.


If you're worried about gas mpg in your classic mustang, you're driving the wrong car. 3.55s will wake the car up but your gas mpg will suffer. I never cared about gas mpg. Generally as hp went up, gas mpg went down, and happiness went through the roof