Gas mileage
#1
Instructor
Thread Starter
Gas mileage
How much gas mileage are you guys getting under normal driving conditions? I’m not beating on my car at all and mileage isn’t that impressive as I’d heard vette’s were? Anything I should look for maintenance wise?
#2
Instructor
I own a 02 Z06 that I drive regularly, mostly interstate driving. I get around 22 to 23 miles a gallon running 80 mph. Car is all stock with only exception of cats being deleted.
#3
Melting Slicks
I love optimizing for fuel economy. Being poor makes you an expert at squeezing every last penny of fuel out of the vehicle.
First thing and most importantly is how you are measuring economy.
You can NOT trust electronic measuring devices. They are for reference, and sometimes very accurate, however should not be relied upon.
The consistent method is as follows:
1. fill tank to top using specific pump
2. drive exact number of miles (must have accurate mileage recording)
3. re-fill to the exact same fuel height (using the same pump-shut off helps here) and divide fuel used over mileage (you know what I mean)
Next some basic rules.
1. Weight is the most important factor. A 3000lb vehicle with any size engine (2.0 or 6.0L) should be able to achieve 30mpg through a manual transmission with a non-parasitic rear (like a ford 9" or something) and proper gear ratios.
2. Automatic transmissions are not all equal. TH400 and 4l80e will use significantly more fuel than say, 700R4, due to the heavier rotating internals and friction. So depending on which auto you are using will affect fuel economy. For reference it seems like 4l80e will reduce mileage around 3 to 5mpg from the 4l60e size trans.
3. Cruise RPM vs engine size is secondary to weight. Large engines need to cruise at low RPM or they will consume excess fuel. Small engines (2L~) don't seem to mind as much.
And the rest of this should help put the nails in this...
Fuel economy posts of the past
https://zilvia.net/f/showpost.php?p=4957504&postcount=7
https://www.thirdgen.org/forums/tech...ml#post4840465
https://ls1tech.com/forums/generatio...l#post19737797
https://ls1tech.com/forums/general-l...l#post19198477
First thing and most importantly is how you are measuring economy.
You can NOT trust electronic measuring devices. They are for reference, and sometimes very accurate, however should not be relied upon.
The consistent method is as follows:
1. fill tank to top using specific pump
2. drive exact number of miles (must have accurate mileage recording)
3. re-fill to the exact same fuel height (using the same pump-shut off helps here) and divide fuel used over mileage (you know what I mean)
Next some basic rules.
1. Weight is the most important factor. A 3000lb vehicle with any size engine (2.0 or 6.0L) should be able to achieve 30mpg through a manual transmission with a non-parasitic rear (like a ford 9" or something) and proper gear ratios.
2. Automatic transmissions are not all equal. TH400 and 4l80e will use significantly more fuel than say, 700R4, due to the heavier rotating internals and friction. So depending on which auto you are using will affect fuel economy. For reference it seems like 4l80e will reduce mileage around 3 to 5mpg from the 4l60e size trans.
3. Cruise RPM vs engine size is secondary to weight. Large engines need to cruise at low RPM or they will consume excess fuel. Small engines (2L~) don't seem to mind as much.
And the rest of this should help put the nails in this...
Fuel economy posts of the past
https://zilvia.net/f/showpost.php?p=4957504&postcount=7
https://www.thirdgen.org/forums/tech...ml#post4840465
https://ls1tech.com/forums/generatio...l#post19737797
https://ls1tech.com/forums/general-l...l#post19198477
The following 2 users liked this post by Kingtal0n:
CorvetteBrent (06-21-2019),
Flatbusted (06-27-2019)
#4
Burning Brakes
Well, I don't do all that.
I just fill up and write down my mileage and go. When I fill up again I hand figure my mileage.
I get around 22-24 mpg on at highway speeds with my 03 vert A4. Not much different in town just cruising around.
I'm happy with that considering it's a 350 hp sports car.
I just fill up and write down my mileage and go. When I fill up again I hand figure my mileage.
I get around 22-24 mpg on at highway speeds with my 03 vert A4. Not much different in town just cruising around.
I'm happy with that considering it's a 350 hp sports car.
The following users liked this post:
CorvetteBrent (06-21-2019)
#5
Pro
I used my '03 Coupe Auto trans with the stock rear for just cruising about the country side. Also keep a log on every fill up with mileage. For the 2 yrs and 3 months I've had this car it's always in the 22 to 26 miles per gallon range.
#7
Instructor
I have a 2000 coupe A4 and on a level highway with no wind I am around 30mpg. My overall MPG on the gauge, which I never reset, is just a little over 25.
#10
Racer
2000 Convertible. I average about 22mpg driving the backroads here in southern MI.
Drove into the big city (Detroit) last weekend for a graduation and was astonished to see the average on the DIC shoot up to 28mpg (80mph on the freeway, 6th gear, A/C on).
Probably the most overlooked feature of the car is its fuel economy. It gets better overall mileage than my 2014 Ford Escape EcoBoost. And that's got a 4 banger!
Had a high school buddy with a '70 RoadRunner (383) that had to get no better than 6mpg, which meant the car looked great sitting in the driveway. lol! I can't think of many older high performance cars that get in the 20's.
Drove into the big city (Detroit) last weekend for a graduation and was astonished to see the average on the DIC shoot up to 28mpg (80mph on the freeway, 6th gear, A/C on).
Probably the most overlooked feature of the car is its fuel economy. It gets better overall mileage than my 2014 Ford Escape EcoBoost. And that's got a 4 banger!
Had a high school buddy with a '70 RoadRunner (383) that had to get no better than 6mpg, which meant the car looked great sitting in the driveway. lol! I can't think of many older high performance cars that get in the 20's.
#11
Instructor
Thread Starter
I’m only getting about 220 miles per tank according to my gauges and I reset them after every fill up. All city driving so fall. Haven’t had it on the highway at all yet.
#13
Le Mans Master
Member Since: Jan 2000
Location: Georgetown TX
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C5 of Year Finalist (appearance mods) 2019
My 2002 C5Z with H/C/I/E (450whp/402wtq) and 3.90 gears gets around 21-25mpg on the highway @ 75mph.
Coolant temps in town traffic with a/c average 205deg and on the road, around 195deg.
Coolant temps in town traffic with a/c average 205deg and on the road, around 195deg.
#17
Melting Slicks
lots of people brag on this, some quoting the instant mileage, means nothing.....
Last edited by Forcedvert; 06-21-2019 at 05:43 PM.
#19
Melting Slicks
Best MPGs I ever had were in a stock coupe 6 speed. Way different than an auto convertible with the performance axle (still get low 20s on the highway with the auto vert) .
#20
Melting Slicks
That kills gas mileage in any vehicle. I have a 2014 Honda Accord and when I sit in Atlanta traffic, my mileage will go from a usual 30 combined MPG to about 20 MPG.
Last edited by bikeriderga; 06-21-2019 at 11:46 PM.