2nd gen gas mileage?
05-30-2005, 07:48 PM
#1
Staging Lane
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2nd gen gas mileage? Hey guys, i have another question about my 79 z28...It's got a lightly modded original 350 with a 4:11 rear and an m22 tranny. What kind of gas mileage can I expect and is there anything I can do to increase it? I'm assuming it's pretty low, single digits even. Just curious if theres any other 2nd gen drivers who can give me a ballpark.
05-30-2005, 08:31 PM
#2
Teching In
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Mt stock '77 with a quadrajet, th350 and 3.08 gears gets about 13mpg in the city driving conservatively, and about 16 or so on the highway. This is up from the 11mpg it got in the city with a 2bbl.
Id expect your car to get ~9mpg or so with those 4.11 gears. Highway you may get lucky and pull over 15, but I doubt it.
If you want better milage, you have a couple of options. What kind of carb do you have? Quadrajets have small primaries which will aid with your gas milage. Second, you could swap out transmissions for someting with an overdrive. Third, you could replace the 4.10 gear with someting like a 3.42. Then lastly, if you are really into it I suppose you could run fuel injection on the car...
All are going to be relatively expensive to do, and honestly, I doubt youll gain more than a mile or 2 per gallon unless you swap out hte m22 for a t5 or preferably t56.
Id expect your car to get ~9mpg or so with those 4.11 gears. Highway you may get lucky and pull over 15, but I doubt it.
If you want better milage, you have a couple of options. What kind of carb do you have? Quadrajets have small primaries which will aid with your gas milage. Second, you could swap out transmissions for someting with an overdrive. Third, you could replace the 4.10 gear with someting like a 3.42. Then lastly, if you are really into it I suppose you could run fuel injection on the car...
All are going to be relatively expensive to do, and honestly, I doubt youll gain more than a mile or 2 per gallon unless you swap out hte m22 for a t5 or preferably t56.
06-02-2005, 11:41 PM
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I have a stock 78 with a 350/th350 and 2.42 stock gears ( ew ) and I get like 12-15 in the city, maybe 18 on highway, max. The way I drive it though, its probably barely 10. 12-15 is only if you feather it, which I only do if Im too tired to pay attention. 
