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Fuel economy

D

dvader

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I had a stock 68 4 spd 383 RR in college that got 15 to 17 mpg. I am restoring a stock 69 auto 383 RR that gets 10 to 11 mpg. Is that what I should expect or are there things I can do to improve my mileage? Any advice or experiane would be greatly appreciated. Tkx
 
We would have to know what you had and what you have. Both engines built to stock specifications, same carburetors, exhaust, ignition systems and same rear axle ratio's? There are lots of things that will effect fuel consumption.
 
I had a 69 383 4 bbl w/automatic in a 65 Sport Fury that got 15-18 mpg (3.23 gears). Lots of variables besides the engine, but 15-18 Highway MPG is doable.
 
My experience is the fuel today has a big Influence on mileage . In 1968 Regular was 95 octane, and "Ethyl" was 98-102.
If I put 106 in my GTX, it will get 13 or so, but on crap fuel, 9 mpg. Also, don't expect the Auto to get the same mileage. I got 22 city with my six speed R/T Challenger (2010) my brother got 16 with his Automatic, exactly what it was rated in 2010. My 69' Cuda four speed 383 gets 14+, but the 383 Auto Coronet pulls 12, City.(on crap fuel)
 
I consistently get single digit mpg. I contribute that to my gearing and larger tires. Albeit I don't have a 383 but gearing plays a big factor.
 
70 383 Challenger with 3.23 got 12-14 but jumped to 17 with a 2.94. It was a stock 4 barrel engine (non Magnum) with factory dual exhaust and AVS carb. Only mod was a Accel dual point with mechanical advance. Had a 66 Mustang Fastback with a stock long block 289 with a Torker intake, 600 DP, headers, 4 speed, 2.80 gears that got 12 in town (DP's suck in town) and 21 on the highway doing 70.
 
I had a stock (new) 1971 383 automatic with 3.23 which got 12 mpg no matter how I drove it. I believe it was equipped with a factory Holley carburetor. Not much can be done without an overdrive to improve that.
 
Last edited:
Thank You all. It appears that ther should be a little room for improvement if I work on it. Thanks again.
 
I got 19-20 mpg with my Coronet on several occasions on road trips with 2.94 SG gearing. That was when I gave a crap about that when it was my daily driver through the early '80s. Now, with a set of 3.23s, I probably get somewhere around 14 - 15 mpg combined town/highway. That's a guess.

361 auto w/Edlebrock 600, MP aluminum dual-plane intake and 3.23 gearset.
 
You guys are killing me.........i get about 6 to 8 mpg with my street wedge..............lots of fun tho.......
 
It seems that the title of this thread should have been 'fuel consumption'...
 
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