30mpg in the stang, possible?

[5spd GT]

I have gained around 3-4mpg after I added my h/c/i to my car...it is working more efficeintly and doesn't have the added "drag" weight of a "supercharger" and the extra "dead" weight either

(I'm not going to let anyone know I want a supercharger though)

 

[ALMOSTFINISHED]

On my last drive to see my GF in Binghamton NY, 187 miles from my house, I cruised with the defrost on (a/c compressor running) doing between 65-70 mph I got 24 mpg. Then coming home without the defrost on and the windows open I averaged 26 mpg. Best I have ever gotten in all the cars I have owned. This is with my 3.73's and my 17 in cobras. I filled it before I left then filled it as soon as I got there to figure it out, then the same when I got home, filled her up before I left then filled as soon as I got home. Not to shabby if you ask me.

Nick

 

[25thmustang]

I personally have seen 27+ in my car on one trip back from New Jersey. It was right around 190 miles and did it on less than 70 gallons of gas (I forget the exact numbers). This is also with running some mid 12s at the track the day before...

I would say 2.73s and driving it like an old lady on all highway and you will be very close!

 

[feifong]

gas

best i got is 20 mpg hwy in my 83 mustang

 

[jrichker]

Install a vacuum gauge and watch it like a Hawk while you drive. Keeping the needle steady & pulling as much vacuum as possible will do wonders for gas mileage.

 

[trbkrb]

It is certainly possible. Keep the car running well, in tune and 2.73 gears and drive 55 and you can get close. I ran a couple of times from Houston to New Orleans a loooong time ago when the speed limit was 55. It was about 380 miles on a single tank of gas each way. I filled up with less than 13 gallons. When I figured the mileage, it was about 29.8 MPG. This was with luggage and my wife on board. While it is certainly possible, it is not practical all the time and definitely not as fun!

 

[darthcual]

Phew! What are you fellas doing to get that 26-29mpg. Best my car can do is 18 city and 24 hwy. I have very low bolt on type mods. Most extreme thing ive done is an e-cam. Wonder what my problem is? Anyway, I think we can all agree that a Mustang is not for ppl concerned w/ fuel economy. I would suggest a good used civic. Maybe you could get one of those neat exhaust all the civics around here have. Hell, the car might already have one.

DC

 

[jackchan]

you guys are killing me..........I get 18.5-19.5 mpg on the hwy! I have just recently tuned my GT up with its 302 and 5-speed. However it is "BONE stock" with the exception of a mac 2 1/2" X-pipe and American Thunder Flowmaster cat back exhaust system (which is also 2 1/2"). I still even have the stock air silencer in the fender!!! Who else is still running the stock air silencer in the fender (of those getting 25 + mpg? I also still have stock gears, which I'm not completely sure of either 2.73s or 3.08's! here is a few tips I plan to start trying in the near future:
1) electric fan
2) K&N air filter with min. amount of surface oil
3) 195degree thermostat..........I hear people running 170 and below suffer from low horsepower and flooding i.e. the computer is actually thrown into a choke loop and therefore uses more fuel and runs actually worse.
4) aluminum drive shaft (actually I already have one installed) I do believe this will help gas mileage thru less rotating inertia.

timing is a big question, would it help to run more or less timing to get better gas mileage. My car is a daily driver that I drive everyday to and from work. I drive over 75 miles a day mostly 4 lane hwy and some interstate.
if anyone has a reply on the timing please advise as I am interested in your opinion.
thanks
Jack

 

[Scorcher2005]

I personally have seen 27+ in my car on one trip back from New Jersey. It was right around 190 miles and did it on less than 70 gallons of gas (I forget the exact numbers). This is also with running some mid 12s at the track the day before...

I would say 2.73s and driving it like an old lady on all highway and you will be very close!

i sure hope you did it in less than 70 gallons! I think you mean 7 gallons....

 

[_jb_]

get a t56....two overdrives,lol and run low gearin with that

It's not two ODs.

 

[RickyB]

my T56's 5th and 6th are under 1:1

 

[HISSIN50]

yeah, i think it depends upon the specs on the T56, but they can have to OD's (which many people think make them sorta useless).

 

[squeeeg]

Most t56's do have 2 overdrives. You can always buy them with different ratios.

 

[Michael Yount]

My best single tank was 26.8 mpg - mildly modded (alum H/C/I/Exh) - 3.73 gears and a T5Z tranny with the .625 5th gear and 225/50/16 tires - revving about 2400 rpm at 70 mph. My car has the aero of a brick - it's shaped just like one.

It seems to get the best mileage running around 65 mph with enough traffic moving a bit faster than me that I can frequently get some 'draft'. This is an element of mileage that is frequently overlooked. There are folks that get better mileage running at 70 mph than 60 mph. The reason is usually because the rest of the traffic is moving along at closer to 70, and you spend more time running behind other cars -- which decreases your aero drag - the chief force to be overcome with fuel use when at speed.

I think hitting occasional 30 mpg tanks in a well tuned, long geared Stang might be possible - but VERY difficult to achieve.

 

[5spd GT]

"I'm not tailgating, I'm drafting"

With the braking performance of these cars (IMO) I think I'll keep the drafting to someone else unless they try me and then I'm going to push that thing under my right foot

I just got 23mpg today (it goes up 1 mile per gallon the last three times I've filled up)...A clutch break-in will do that

 

[I_AM_CANADIAN]

"I'm not tailgating, I'm drafting"

 

[vristang]

Install a vacuum gauge and watch it like a Hawk while you drive. Keeping the needle steady & pulling as much vacuum as possible will do wonders for gas mileage.

Finally someone on the same wavelength. The best fuel economy a vehicle will experience on the highway will be with Coast and Burn @ around about 60-65mph. Basically when you get on the freeway open up the throttle to just under WOT to avoid the rich mix at WOT. If the target speed is 65mph, then when you hit 70 put the trans. in Neutral. Allow the engine to idle while the speed drops to 60mph. Always use fifth when you do this to keep the RPMs per mile as low as possible.
Expect to piss off every other driver on the road!
Also, it gets a little old after an 1.5 hrs on the road!
I have tried this in my 408W and gained around 2-3mpg (avg over a couple of tanks). I was still doing some city and low speed back road driving when I tried this, so it should be better with only highway miles.

 

[HISSIN50]

Finally someone on the same wavelength. The best fuel economy a vehicle will experience on the highway will be with Coast and Burn @ around about 60-65mph. Basically when you get on the freeway open up the throttle to just under WOT to avoid the rich mix at WOT. If the target speed is 65mph, then when you hit 70 put the trans. in Neutral. Allow the engine to idle while the speed drops to 60mph. Always use fifth when you do this to keep the RPMs per mile as low as possible.
Expect to piss off every other driver on the road!
Also, it gets a little old after an 1.5 hrs on the road!
I have tried this in my 408W and gained around 2-3mpg (avg over a couple of tanks). I was still doing some city and low speed back road driving when I tried this, so it should be better with only highway miles.

hmm, too bad auto manufacturers did not think of that instead of cruise control. i will stick with CC for best economy.

JR is right about the vac gauge - i run one in the 88 (still SD) and on some of the older stuff. just a good gauge to have.

 

[Allforspeed]

i've gotten 28 mpg a bunch of timeson the freeway, luck to get double digits in san francisco city driving though , my tires are filled up a bit past recommended, i got a full exhaust, under drives, full synthetics and stock gears, but i've also got 135K miles on this car and a stock belt fan, also weights almost 3400lbs with me in it, with stock gearing in a notchback i dont think 30 mpg is impossible, i have seen my friends SS ls1 camaro get 32 mpg on the freeway by the way on road trips, i figure keep the stock gears and get a nitrous kit with the 400$ it would cost for the install!

 

[vristang]

hmm, too bad auto manufacturers did not think of that instead of cruise control. i will stick with CC for best economy.

There was a big push for it at one time, probably the early 80s. The US consumer would never accept such a driving routine! Japan is the only place I have heard of that required it, just not sure of the time frame.