Gas mileage question for a 289
 

What kind of gas mileage could one expect, roughly, from a stock 289 in a 66 Mustang? Assuming the car is 100% stock. I'm kinda, sorta, looking at one and don't know much about it yet. I'm needing something with at least around 20 mpg/tank. I don't know what tranny it has, though, or rear gearing. It's a hardtop/vinyl top. No vert.

I used to average about 16 mpg with the 289, but I had a 4 bbl. and used it often.

-red

I bought my '66 coupe in '68 with 17,000 miles on it. It had a 200 hp 289, single exhaust, 2bbl carb, C-4, and a 2.80 axle. I dindn't baby it and always got 16 mpg average city and highway.

Now I get 12 1/2-13 mpg but have a heck of a lot more fun.

Rev

You ought to expect 14 to 16 mpg.

Well Rev your doing better than me. I get about 10.5 mpg around town. Rediculous I know considering the fact we have almost the same things. Everything stock even the 2 barell I got about 16. On the other hand the torino with a 4 barell edelbrock aluminum intake headers dual exhaust roller rockers gets about 18-20 mpg freeway.

I have driven my old 64 1/2 Diane (289) to Pennsylvania and back several times from North Carolina.

On the highway she got 12 MPG. In City she averaged 7.5 MPG. That was before I rebuilt the top end and added the 1.7:1 rockers and the ported, shaved, CC'd heads. Now she probably gets Less.

I'm curious on what I'd get on mine. Any estimates for mine.
351-4bbl, 3.73 gears in the rear, Mach 1, my signature tells most.

My 66 with a 2v 289 stock, 3 speed manual and 2.80 rear got between 20-22 on the highway. But it also has no power robbers; no ps, air, etc.

I get 10 -12 with a 289 2bbl headers, but it's so bad because of the cam and timming chain, both need replacing bad.

I get ~10mpg. 289, 351 heads, 625 cfm 4 barrel, 4 speed, 389 gears.

I think the 389 gears is what did it. I have 290 in mine

Yeah I don't have a tach, but on the highway its screaming at me!!!

What about the freeway.

I'll let u know what I get when I replace my cam. I think it will stay the same because it's kinda a heavy cam.

I ALWAYS got about 14 mpg with mine. this is experience gathered from several different Stangs. The best I ever got with a carb was probably 16-17.....and that included quite a bit of highway time AND that was with the 5-speed.

:D now with the fuel injected 302/5 speed combo, I am pulling in a consistant 20-21.....and I wonder what I could get on a trip.