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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

gas mileage

  • Thread starter Thread starter ike34
  • Start date Start date Aug 30, 2004
I

ike34

Member
Jan 16, 2004
156
12
19
Waterloo, IA
Aug 30, 2004
#1
  • Aug 30, 2004
  • #1
What is the gas mileage for a stock 1991 5.0L mustang, like city and highway numbers?
 

TRWXXA

Member
Jan 18, 2003
190
1
19
RIGHT BEHIND YOU!!!... Made you look.
Aug 30, 2004
#2
  • Aug 30, 2004
  • #2
As the advertisements say, "Your mileage may vary."

This weekend, I averaged 24mpg on a 700 mile round trip. All interstate, and I kept my speed down around 72 mph because I was convoying with someone else. Pretty good considering I have 3.73s.

This is up from the usual 19 to 21 mpg I was getting. A new air filter, some injector cleaner, and some new vaccum lines probably helped as much as keeping my foot out of it.

I imagine you could do just as well with your '91.
 

BelueLX

Founding Member
Jul 10, 1999
1,195
1
0
Aug 30, 2004
#3
  • Aug 30, 2004
  • #3
i get around 270 miles on 13.3 gallons to and from work stop and go in my 88 LX. thats 20.3mpg. never ran a full tank of gas out highway driving.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Aug 30, 2004
#4
  • Aug 30, 2004
  • #4
15 in town if im lucky.
 
S

sidewayzisbest

New Member
Feb 6, 2003
427
0
0
Lexington, SC
Aug 30, 2004
#5
  • Aug 30, 2004
  • #5
umm depends on your driving habits =p
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Aug 30, 2004
#6
  • Aug 30, 2004
  • #6
sidewayz is right - driving style and traffic are HUGE factors making it difficult to compare. In big metro areas where a driver might spend a lot of time in bumper to bumper traffic during a commute, you might be doing really good to see 13-15 mpg. For more suburban/rural areas where 'around town' means less bumper to bumper and more 30-45 mph cruising, the same car might get 18-20 'around town'. Highway comparisons are pretty valid - as long as the speeds are similar.

Mine has mild mods (about 270HP/330 torque crank numbers) and the equivalent of what would be 3.90 gears in a stang (5 speed, .625 5th). I've consistently gotten 18-19 mpg in town (suburban - very little stop and go), and recently completed a 525 mile round trip running 65-70 on the Interstate - used 20.0 gallons -- 26.3 mpg. Same engine in a Stang I think might get a mile or two better highway numbers due to the Volvo's 'brickish' aerodynamics.
 
I

Idwitheld-1`

New Member
Nov 30, 2003
335
0
0
Portland Oregon
Aug 30, 2004
#7
  • Aug 30, 2004
  • #7
15.9 hwy / city combo driving.
12 city

ouch...that sucks.
 

ALMOSTFINISHED

Member
Jan 8, 2004
315
0
17
Westchester County NY
Aug 30, 2004
#8
  • Aug 30, 2004
  • #8
Boy, everybody is real lucky there. I do mostly stop and go driving and get about 140 miles out of a tank. my best was 200 out of a tank on a road trip. I only run 93 octane, its been tuned, new 02's and all. The car has done this the 3 1/2 years of ownership. At first i thought something may have been wrong but when my friend bought a 92 gt and he was getting the same out of a tank with stock gearing as opposed to my 3.73's I felt alot better.
Sorry to cut short but i gotta go fill'er up!

Nick
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Aug 30, 2004
#9
  • Aug 30, 2004
  • #9
Nick - have you tried running lower octane? Unless it's keeping you out of detonation with your timing, it may pick up a mile per gallon or so if you drop back to 89 or 87 octane. There's no benefit to running 93 unless it's keeping you out of detonation -- it's harder to ignite and burns fractionally slower than the 87. Mine's running 16-18 degrees of initial, 32-34 degrees total and with aluminum heads, I'm still running 87 octane without any trace of detonation.
 

super302

I'd do anything for free Bapples
May 29, 2004
2,878
1
0
Davenport, IA
Aug 30, 2004
#10
  • Aug 30, 2004
  • #10
i squeezed out 19 all city once, i could prob. get 20 if i try...never been on the interstate
 
S

sidewayzisbest

New Member
Feb 6, 2003
427
0
0
Lexington, SC
Aug 30, 2004
#11
  • Aug 30, 2004
  • #11
i usually get 18-20 mpg its mainly in your tune ....but also i do have to give it 2nd gear a couple times =p
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Aug 30, 2004
#12
  • Aug 30, 2004
  • #12
super - we gotta get you outta Iowa on the Interstate!
 

ALMOSTFINISHED

Member
Jan 8, 2004
315
0
17
Westchester County NY
Aug 30, 2004
#13
  • Aug 30, 2004
  • #13
Michael- I never thought of that, but to be honest with you i may give it a shot and see if i can pick up any. I assumed with the advanced timing that i would get pre det. I'll try it this week and post a reply.

thanks very much for the info. any help in gas milage would be great. super averages about $2.38 a gallon here.

thanks again

Nick
 

super302

I'd do anything for free Bapples
May 29, 2004
2,878
1
0
Davenport, IA
Aug 30, 2004
#14
  • Aug 30, 2004
  • #14
Michael Yount said:
super - we gotta get you outta Iowa on the Interstate!
Click to expand...
I know
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Aug 31, 2004
#15
  • Aug 31, 2004
  • #15
Nick - if nothing else, it'll save you per gallon. There's a common myth that the higher octane fuels are somehow 'better' for your car; but unless they're keeping you out of detonation at the timing you want to run, it's just wasted money. There's no other benefit at all.
 

roush 97

New Member
Aug 28, 2003
86
0
0
Illinois
Aug 31, 2004
#16
  • Aug 31, 2004
  • #16
I get about 24 mpg highway with stock gears. City it can drop to 17 or 18 if I really keep my foot in it. Still better than my 6 banger Ranger that gets about 14 or 15 no matter what..
 
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