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  • 1974 - 1978 Mustang II Talk & Tech

VERY IMPORTANT!!!!!

  • Thread starter Thread starter admaster99
  • Start date Start date Jun 9, 2004
A

admaster99

Founding Member
Jul 5, 2002
73
0
0
Iowa
Jun 9, 2004
#1
  • Jun 9, 2004
  • #1
Alright, I know there has been alot said about gas mileage for Mustang II, but I have been realizing something that isn't right. At least I think. Well I got this nice mustang II cobra about a week ago. And it runs good, but the gas mileage is horrible. I don't know what it is, but I was out tonight drove on a 20-25 min drive about I think 10 miles give or take a little and it took 1/4 a tank. Yeah I know V8's suck gas and these cars have smaller gas tanks I think it cost around $25-$30 dollars to fill it up. And I'm used to a little 4 cylinder, but that can't be right can it. Thats insane, it is suped to about 350 hp thats what the guy said with a 4 barrel edelbrock 650 cfm. Thats driving at at 55 mph with the rpm at about 2800. I was thinking that the clutch was going out because it kind of suffered a little in performance, but I'm starting to think that its something with the engine maybe it's running to rich or something. Some examples are when I take off in first it kind of hick upes and stumbles a little bit almost dying and I notice that when I'm driving it kind of stutters alittle bit. The first day I had it, it seemed like it drove better a lot easier to roast the tires, but now all i can get is a good squeel. WELL LET ME HEAR YOUR IDEAS(this car has been sitting for 2 years!)NEED HELP THANKS!
 
C

cobraii74x

New Member
Aug 27, 2003
253
0
0
Altoona, PA
Jun 10, 2004
#2
  • Jun 10, 2004
  • #2
The classic "car runs great til ya get it home".. check all the usual see if it is running rich the condition of the spark plugs.. maybe your plugs are bad .. check plug wires ( they do corrode, i know ) any black smoke or anything.. ? if your burning oil it might take more gas to combust and that would cause bad gas mileage ? ..low tire pressure ... just check around man... or maybe thats just what your gonna have to deal with! ...
 

1970impala

Please God, somebody find me some WHITE CARGO PANE
Founding Member
Jan 22, 2002
1,450
2
38
Pennsylvania
Jun 10, 2004
#3
  • Jun 10, 2004
  • #3
wrong fuel sending unit? incorrect gas tank? gas leak? brakes hung up? emergency brake on? emergency brake cable hung up?
 
T

THE COBRAMAN

pig 'rassler
Founding Member
Mar 11, 1999
1,974
0
36
Oklahoma
Jun 10, 2004
#4
  • Jun 10, 2004
  • #4
admaster99 said:
I don't know what it is, but I was out tonight drove on a 20-25 min drive about I think 10 miles give or take a little and it took 1/4 a tank. Yeah I know V8's suck gas and these cars have smaller gas tanks I think it cost around $25-$30 dollars to fill it up. And I'm used to a little 4 cylinder, but that can't be right can it.
Click to expand...


Basing fuel economy on indicated usage is insane. Fill it up on a level surface, run it till it's almost empty, then refill at the same place.

Only then can you get a determination of actual usage.

Mine stays over full a LONG time, but the needle dropping on the last quarter is like an anvil out a window.

Might check the hose between the aux and main tanks for condition, also the aux tanks are pretty famous for leaking.
 
T

TRIT0N

New Member
Jun 9, 2004
8
0
1
Jun 10, 2004
#5
  • Jun 10, 2004
  • #5
aux tank?
explain
my buddy has a 77 cobra II and we need a tank but i never saw an aux
 

jeffnoel

Founding Member
Aug 31, 2002
1,638
5
37
Clovis, CA
Jun 10, 2004
#6
  • Jun 10, 2004
  • #6
TRIT0N said:
aux tank?explain
my buddy has a 77 cobra II and we need a tank but i never saw an aux
Click to expand...
If it's a V8 car it was standard equipment. It's mounted in the drivers side rear wheelwell behind a removable metal plate.
 
Z

zwhitr

Founding Member
Aug 26, 2001
847
0
16
Goldsboro, NC
Jun 10, 2004
#7
  • Jun 10, 2004
  • #7
THE COBRAMAN said:
Basing fuel economy on indicated usage is insane. Fill it up on a level surface, run it till it's almost empty, then refill at the same place.

Only then can you get a determination of actual usage.

Mine stays over full a LONG time, but the needle dropping on the last quarter is like an anvil out a window.

Might check the hose between the aux and main tanks for condition, also the aux tanks are pretty famous for leaking.
Click to expand...


agreed not a very accurate way to measure actually usage

think about how many times you roasted the tires stop and start

go on a long drive on the interstate

Lets do the math

15 gallon tank ---- 15/4 =3 3/4 gallons per quarter 3.75 x 8 MPG = 30

not overly excessive in my book. If you were doing a few burn outs and a gear jammin session along the road.

ps the shape of the II tank has a section that rises up and is above the sender in addition the the reserve tank in the fender

As cobraman said first half is like 2/3 tank and the second half is the last 5 gallons it goes quick
 
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