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so went from full tank to empty and calculated my mpg. im getting about 8 mpg right now and i know with my engine tranny 318/727 i should be getting atleast more than that. I was hoping for at least 12 mpg but 8!!! for one idk if its weight related bc my trunk is full of junk to the top, il be emptying that out this weekend to where all im going to have in there is a jack, a toolbox and a spare, hopefully that will get me to 9 mpg ha. what else should i look into for why my mpgs are so low? i definitely need to get this number up. Thanks!
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also forgot to mention it has a carter 2 barrel carb, 15in. wheels, all stock with mild cam, dual exhaust.
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Stuck heat riser
Choke not opening all the way
Not sure about the mild cam? how mild ?
compression ok ?
tire pressure
heavy right foot LOL
The Idaho Andy
I love the smell of race fuel in the morning
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ok this may be a dumb question, but wheres the heat riser, how do i check it and what does it do? 2nd the choke is functioning fine, opens all the way when warm. this may be bad but when i redid the heads i lost my paperwork for the cam i bought, therefore i cannot remember the cam, all i can remember is it is an RV mild cam, i know ppl will probably hate on me for not keeping the paperwork or remembering the cam, but hey i was 18 i didnt care just wanted her running lol, compression, not sure havent checked it as i dont have a compression tester. tire pressure 35 lbs each tire. and i drive it very lightly, i dont ever get on it, i just cruise 60mph all day. i travel 20 miles to work straight highway and 20 miles back everyday. only 2 stop signs the whole way.
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Since you have dual exhaust you can get behind car with it idling and see if both sides feel even flow.
The heat riser is a valve the looks similar to your choke valve and when working properly it closes when cold to force heat back up through intake manifold to warm engine faster. And opens fully when hot to free exhaust. It's located on the right exhaust manifold right above ex. pipe flange.
I hope this helps explain it ??
The Idaho Andy
I love the smell of race fuel in the morning
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yes both pipes flow freely, ok i know what youre talking about ive always seen the heat riser and wondered what it is. i know for a fact its rusted open, it doesnt move. does that effect the mpg much?
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If it's open your OK there, just making it a little cold blooded in morning thats all
The Idaho Andy
I love the smell of race fuel in the morning
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oh shes VERY cold blooded in the morning , but when shes warm she purrs, well actually more like chugs haha but also i havent messed with my carb, i know it idles really good but maybe it could be running too rich? would that effect the mpg?
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How's your timing? Do you have points or electronic ign?
President, New England chapter of Coronetaholics anonomous.
Posts: 37
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sorry guys i dont really know my technical specs like how far out my distributor is, when i was 18 again, i was having trouble getting my car to run smooth and didnt know didly squat about timing other than it needs to be in time. my neighbor who is an old school chevy guy got it timed and running smooth for me. i do know it has the pertronix electronic ignition.
