Vintage Mustang Forums banner

1 - 8 of 8 Posts
G

·
Guest
Joined
·
0 Posts
Discussion Starter #1
Ever since I got my '66 289 on the road, it has had horrible gas milege. It was originally a 2v I put on a edelbrock 4v carb/intake. Still as bad as ever. I know the 4v doesn't help but it should be better then it is. My friends 350 Nova gets better milege then me. Any suggestions how to correct this? Also my fuel gauge doesn't work correctly. I can fill up the tank but the needle only goes to just below 3/4 of a tank. Do I need a new sending unit? Thanks for the help.
 

·
Registered
Joined
·
6,911 Posts
good condition ignition , including timing

may need a sender...maybe tank or instrument cluster isnt grounded well now.....
 

·
Registered
Joined
·
2,987 Posts
What kind of milage do you get?
I get 6 in the city and 10.5 on the highway.
I also have a 429. /forums/images/icons/smile.gif
 

·
Registered
Joined
·
2,466 Posts
It sounds like the sending unit. If the float gets a pin hole, it will sink some.

As far as milage, it really varies. My car got 18 mpg when it had a milder 289, and 2.80 gears. "More Power" mods to the engine and 3.55 gears dropped it to 13 mpg with a C4 tranny.

Installation of the T-5 got me back up to 19 mpg on the highway. /forums/images/icons/smile.gif
 

·
Registered
Joined
·
1,106 Posts
Define horrible gas milege. What is your MPG in City, Highway and how do you drive? Is the A/C always on and do you have huge tires that need air? The biggest factor in MPG is the driver. A lot of time, a performace tune up will increase MPG and power by making it run right. Give more details.
 

·
Registered
Joined
·
4,193 Posts
You say you know your new 4 bbl doesn't help matters; but often times it may. If you can keep your foot out of it, a 4 bbl will give you better mileage than a 2 bbl. I know my Edelbrock does. And it may only be a mile or so per gallon, but that ads up!
 
G

·
Guest
Joined
·
0 Posts
Discussion Starter #7
As a comparison, I get 10-11 MPG on the highway with a modified 351C 4V which is slightly better than the 9 MPG it got when new.
 
G

·
Guest
Joined
·
0 Posts
Discussion Starter #8
As for the gas milege, I haven't had the opportunity to check it accuratly. My driving (in this car at least) is grandpa-ish. It's not like I floor push it hard at all. I don't have a/c and my tires are your typical 15" wheels. Thanks.
 
1 - 8 of 8 Posts
Top