Miles per gallon
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Joined: Mar 2008
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From: Fairfield N J
Miles per gallon
Just got my 77 on the road for the first time. The car has been sitting many years before I got it. Here is my problem I am getting about 8 miles to the gallon. Is this normal?? Where should I start to try and improve the gas milage? The Carburator looks like it could use an update. I know there are problems with the choke. I have done nothing to the engine except plugs and wires. 
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From: Wellington, FL
St. Jude Donor '11 thru '25
8 miles per gallon sounds low even with all town driving. I think my '76 gets around 15 on the highway and probably about 12 in town. I would give it a thorough tune up including new distributor cap and air and fuel filters. If the choke is on a lot, that will make the engine burn quite rich and drop your mileage. It should be adjusted properly. I'd also change all fluids and rad. hoses if you haven't already done so. 
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From: Wellington, FL
St. Jude Donor '11 thru '25
I would contact Lars, a Q-jet expert who has helped many forum members.
http://forums.corvetteforum.com/show...highlight=lars
http://forums.corvetteforum.com/show...highlight=lars
Melting Slicks
Joined: Mar 2006
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From: Orange Park Fl
My '81 got about 15 city/18 highway when I got it stock (185hp). Now I get 18 city and 23 highway with around 375 hp. Efficiency = power + economy!
Fix your carb (no, don't replace it), check the exhaust manifolds for leaks (usually sounds like a ticking noise), replace your cap, plugs and wires and set your timing. God bless, Sensei
Fix your carb (no, don't replace it), check the exhaust manifolds for leaks (usually sounds like a ticking noise), replace your cap, plugs and wires and set your timing. God bless, Sensei
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From: Henderson Nv-Rohnert Park/Sonoma C o. ca/born in NY Rockaway Beach.
I Have a 77 and im getting about 10city and about 15 hwy when im not trying to keep up with the c5 and c6's on our cruises.
i would bet that a rebuild on the carb would show a big diff
i would bet that a rebuild on the carb would show a big diff
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Joined: Mar 2008
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From: Fairfield N J
When you say fix the carb? are you suggesting I get a rebuild kit and go at it? I was just checking and the idle is high, if I lower the idle the car stalls it is either high or nothing. Also looked in the carb and it seems gas is dripping from in between the jets at the back part of the opening. I hope I am explaining it correctly.
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Melting Slicks
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From: North Bellmore Ny
St. Jude Donor '09
Race Director
Joined: Sep 2001
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From: Wellington, FL
St. Jude Donor '11 thru '25
Me too. 
Tech Contributor
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From: At my Bar drinking and wrenching in Lafayette Colorado
If the car has been sitting for a while and is getting poor mileage, I can tell you with almost complete certainty that your ignition system needs to be repaired - fixing the carb alone won't do it for you. Your vacuum advance is almost certainly ruptured, and your centrifugal advance is either gummed up or rusted up. You need to fix your distributor first by freeing up the advance mechanism and installing a new vacuum advance. Then, set your timing to 36 degrees total. After that, do the carb to finish it off.
Lars
Lars