what kinda gas milage in a 302?

[crow_waxer]

hey all, i have a 79 for fairmont at home, and i am going home for 3 weeks.  right now, it has a 3.3 liter, (200ci) inline six in it, which, runs ok, but that thing is about wore out, and has pratically no power left to it.  so, i was gunna try to get a 302, or, maby even a 351 to put in the car to replace the straight six that is in there now.  but, the question is, what kinda gas milage do u think a 302 or, 351 would get in a car like that?  the car isn't huge, and it is pretty lite, so i figured a 302 wouldn't do to bad on gas, but, the 351 will suck more, coz it is bigger and all, but didn't think it would be to terrible either.  what do u all think?  coz i am debating to put another motor in it, or just try to fix up the one i got now, which doesn't do to bad on gas, it just has no power to it at all, lol.  thanks

[Graybeard]

The last time I had a 351 it was in an '85 Bronco with the three speed auto transmission and got 12 mpg. It was the HP351 with four barrel carb and boy would that truck run but you weren't gonna do better than 12 mpg no matter how you babied it. Now a car ain't a truck and you should do better but I think you'd be kidding yourself to think it would give much over 15 mpg even in the car.

My '92 Bronco had the 302 EFI engine hooked up to the four speed auto transmission and it would easily do 16-17 mpg in routine day to day driving and better on trips. Put one similar to it in your car and you should come close to 20 mpg day to day I'd think.

[crow_waxer]

thanks a lot greybeard, i kinda knew it wouldn't get outstanding gas milage with either engine, sepecially a 351, which, would almost be big of an engine for the car anwya, (if there is such a thing  )lol.  i thought the 302 would do somewhat decent on gas, but wasn't to sure.  thanks for the help

[30-30man]

The 302 is not going to be a gas saver but it will run forever as long as the transmission holds up.  I agree with GB.  I had a 79 Ford F150 with a 351M.  It had a two barrel carb on it and the best it ever did was 15mpg.  You had to lean the crap out of it just to get that.   Good luck with the build.  If you are concerned about gas mileage, why don't you just get the I6 rebuilt?  It would be cheaper anyways.

[GrassLakeRon]

Hi,

     I had an 83 Grand Marquires.  It had a 302 and an AOL trans behind it.    300k miles and no issues.  Gas mileage ran 17-22 mpg depending on how fast I drove.  22 at 55.  20% worse at 70, which it true in any car.  I also had a 79 Grand M as well.  It had a 351W with a Variable ventura injection system.  That meant issues from the start.  A 302 with a 242 cam and a small 4 Brl carb with a C4 should be great, low 20's.

Good Luck

Ron

[Buckskins & Black Powder]

we had 2 f250s with the 302 and we soon found out why they came with 2 fuel tanks. Both were 4x4s and got 12mph empty. We hauled a 76 buick electra 225 to fender with the one ford and got 6mpg