rebuilt gm 350 crazy bad mpg
#1
rebuilt gm 350 crazy bad mpg
Hello love the site. my question is I have a rebuilt gm 350 swaped into my 95 jeep wrangler my tire size is 35 12.50 an my MPG doesnt just suck it really sucks I just got it back from the shop an it had a half tank an 35 miles later I was on E now I know I should get bad mpg but should it be that bad I think my gears are 4.11's also what should a 86 gm v8 get mpg. sorry my gas tank is a 15 gallon if that helps
#2
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Car: 91 RS
Engine: 350 vortec
Transmission: T-5
Axle/Gears: not the best not the worst
Re: rebuilt gm 350 crazy bad mpg
well where do i start...
what did you do to the engine CR? cam? heads? what are you running for fueling? carb/efi done any tuning?
why do you think you have 4.11 gears?
i have a 91 v8 that is getting about 8-9 MPG but i am guessing that it is slightly different from yours
what did you do to the engine CR? cam? heads? what are you running for fueling? carb/efi done any tuning?
why do you think you have 4.11 gears?
i have a 91 v8 that is getting about 8-9 MPG but i am guessing that it is slightly different from yours
#3
Re: rebuilt gm 350 crazy bad mpg
well I know it has 4.11's an it has a carb I really dont know what was done to it I should find out an get back to you but it is sucking gas like a thursty ginny
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Car: 91 RS
Engine: 350 vortec
Transmission: T-5
Axle/Gears: not the best not the worst
Re: rebuilt gm 350 crazy bad mpg
well have you changed anything on the carb? what carb is it? what do your plugs look like.. does it smell rich at idle see puffs of black smoke at any point?
#5
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Re: rebuilt gm 350 crazy bad mpg
I'd wonder if the gague is reading accurately or if the shop didn't "test drive" it while they had it. It's tough to drink half a tank in 35 miles, unless you have a fuel leak. If it was burning that much gas you'd be belching black smoke out the tailpipe and it would be running bad to the point you couldn't help but notice it.
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Car: 88 GTA
Engine: 355
Transmission: TH350
Axle/Gears: 3.42 Auburn Pro
Re: rebuilt gm 350 crazy bad mpg
I had a 96 Chevy K1500, and for awhile ran 35x12.50 Thornbirds. It had 3.73 gears. It sucked gas like you would not believe. It takes a lot to turn tires that big. I estimated my mpg in the 6 to 7 range.
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Car: 1984 Z28
Engine: SLOW carbed ls
Transmission: TH400 with brake, 8" PTC converter
Axle/Gears: moser 9" 4.11
Re: rebuilt gm 350 crazy bad mpg
my suburban has 36s, 3.73 gears, no overdrive and tips the scales at 8200 pounds and still gets 8-9mpg in the city and 11-12 on the highway. 5.7L tbi truck, just FYI
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