Gas mileage
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Gas mileage Well my 02 car has never really gotten the mpg that my 99 pulled.
I took my first road trip in several years this past weekend and the car only did 20mpg. What the hell. Any suggestions?
I have 4.10's, 224,224, headers. I drove 74 all the way and not really getting on it that much.
Any thoughts?
I took my first road trip in several years this past weekend and the car only did 20mpg. What the hell. Any suggestions?
I have 4.10's, 224,224, headers. I drove 74 all the way and not really getting on it that much.
Any thoughts?
it's those 4.10's, they're not meant for gas mileage. and is your car an A4 or M6? I have 2.73 gears and with the A4 I got maaaybe 28mpg highway doing about 80. I swapped to an M6 with the same gears and even with my 228/222 .558 cam, lt headers, ory, corsa cat-back, fast intake manifold, I still get over 32 average on the highway doing 80-85. of course they're 2.73's but I'm sure if I went to 4.10's it would really decrease my gas mileage.
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Yes it is a m6. I guess it is the gears. I was turning about 2000- 2200, but man I didn't think it made that kind of difference. My 99 with 3.42 got 26 - 27mpg.
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it is a good thing I don't drive it daily or on road trips anymore. I guess I will have to cruise a little slower next time.
I do need to change my fuel filter and clean the maf with some maf cleaner.
I do need to change my fuel filter and clean the maf with some maf cleaner.
400 more rpms at highway speed is gonna do that for you....not to mention the cam.
was the car street tuned or just WOT? that could pick up a little mileage.
but honestly...what were you expecting?
although my cammed car gets 25-26mpg with stock gears (m6) doing 75-80mph. and my part throttle tune is horrible.
was the car street tuned or just WOT? that could pick up a little mileage.
but honestly...what were you expecting?
although my cammed car gets 25-26mpg with stock gears (m6) doing 75-80mph. and my part throttle tune is horrible.
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Those gears will change your MPG..LS series engines are not hard on gass till you get them above 2000 RPMs..when my car was stock I got 28-29 MPH on the highway..after the H/C and mods it still gets about 26. When I ran 4.10s for about 40,000 miles my MPG went down to 22.
You may gain a couple MPGs if you spent the time to "street tune" the VE table and MAF tables for maximum efficiency. I picked up about 3 MPG on avg and 5 on the freeway when I did mine. But it took a decent amount of time.
Couldn't agree more, thats part of the reason I'm converting to an LS1. I'd give anything to knock down 20mpg with a small block. Pretty hard to do with one that makes any kind of power.
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Well I have to agree. I did decide to get some maf cleaner. It was a little dirty and thought that may help some. If not, I hope it at least may do something at WOT!
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400 more rpms at highway speed is gonna do that for you....not to mention the cam.
was the car street tuned or just WOT? that could pick up a little mileage.
but honestly...what were you expecting?
although my cammed car gets 25-26mpg with stock gears (m6) doing 75-80mph. and my part throttle tune is horrible.
was the car street tuned or just WOT? that could pick up a little mileage.
but honestly...what were you expecting?
although my cammed car gets 25-26mpg with stock gears (m6) doing 75-80mph. and my part throttle tune is horrible.
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Oh I do enjoy the gears and will not go back. I really on drive the car from time to time in town and almost never on the road. I have hp tuners for the car, but does anyone know how to tune with that program? I would love to learn.
If you already own HP Tuners you're at least halfway there. Look on their forum, what you want to do is VE (volumetric efficiency) and MAF tuning. Since your car has a tune you should really just focus on the "cruising cells" to get better mileage. You can do this type of tuning without a wideband using long term fuel trims (LTFT) but it is a lot easier and faster with a wideband.
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I make sure you speedo is set correctly. I know I got that with 3:42 gears. I did find my tire size was incorrect so I should have had a few more miles over the trip, but I do think there is some in town tuning needed.
IF a tune is COMPLETE (including part-throttle), the highway miles should be extraordinary compared to the city miles.
All extreme motor mods just make it a more efficient breathing machine. On the highway with far greater momentum than the stop-and-go of city driving, one will reap the gas-mileage benefits of that efficiency . . . IF the tune is COMPLETE.