Calculated Gas Mileage (Average)
Thread Starter
Melting Slicks
Joined: Jul 2007
Posts: 2,939
Likes: 7
From: Simpsonville SC
St. Jude Donor '09-'10
Calculated Gas Mileage (Average)
I have had my 99 Convertible for a couple of months now. Every time I fill up (only with BP Premium), I check my mileage. The DIC always computes my average 2 - 3 MPG higher than actual usage.
Does anyone know if there is a way to tune the DIC to calculate Average MPG better?
Also, my vert is completely stock. I ony average about 19 MPG. I drive it soft most of the time, and only 'get on it' maybe once a day.
What is the first this I can do to up my MPG?
Does anyone know if there is a way to tune the DIC to calculate Average MPG better?
Also, my vert is completely stock. I ony average about 19 MPG. I drive it soft most of the time, and only 'get on it' maybe once a day.
What is the first this I can do to up my MPG?
Le Mans Master
Joined: Dec 2000
Posts: 9,900
Likes: 1,841
From: Hot Springs AR
No, there's no way to adjust the mileage calculations. My actual mileage is about 2-3 mpg lower than the calculator.
As far as your overall mileage is concerned, it totally depends on the kind of driving you're doing; urban, rural, hwy, etc. Also, "getting on it" drops it in a hurry.
Finally, are you using E10 fuel? If so, that's worth about a 10% drop (due to the lower BTU content of ethanol).
HTH, and have a good one,
Mike
As far as your overall mileage is concerned, it totally depends on the kind of driving you're doing; urban, rural, hwy, etc. Also, "getting on it" drops it in a hurry.
Finally, are you using E10 fuel? If so, that's worth about a 10% drop (due to the lower BTU content of ethanol).
HTH, and have a good one,
Mike
Team Owner
Joined: May 2001
Posts: 36,836
Likes: 244
From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
I agree with VetteDrmr. No way to "adjust" or calibrate the DIC that I know of either.
FWIW, my DIC has consistently showed 5-10% higher numbers than actual measured mpg ever since I've had the car (8 years).
HTH
FWIW, my DIC has consistently showed 5-10% higher numbers than actual measured mpg ever since I've had the car (8 years).
HTH
Thread Starter
Melting Slicks
Joined: Jul 2007
Posts: 2,939
Likes: 7
From: Simpsonville SC
St. Jude Donor '09-'10
Pro
Joined: Aug 2007
Posts: 676
Likes: 2
From: Amherst VA
mine averages 19.5, most of my driving is around town and I do put my foot in it from time to time (OK,OK, everytime I get a chance). I'm quite happy with the MPGs , I don't want to just putt-putt around in the interest of saving a few drops of gas.
Out on the highway I get about 33 @ 65 with CC on.
Out on the highway I get about 33 @ 65 with CC on.
Advanced
Joined: Jul 2007
Posts: 55
Likes: 0
If your state or region doesn't require E10 gas, consider yourself lucky. It's mandatory in most of the country by now. So, we don't have a choice, regardless of brand. But, you might want to take a look at the pump next time. You might be in for a surprise (assuming they are required to post that information, of course).
Race Director
Joined: Jan 2006
Posts: 10,554
Likes: 33
From: Not on either liberal coast.
Are you clearing everything on the DIC with each fill up?
I'm at 5,200 ft altitude and have been using only CHEVRON fuel. I drive my car only on weekends and generally take 100-125 mile round trips through the mountains to 7,000 ft altitude with some very challenging twisties and cut backs in northern AZ. I never average less than 20.5 mpg on the DIC and by hand computations, it's usually 20.1 to 20.3 mpg at the lowest. My car is also stock with the exception of a K&N drop in filter in a modified Z06 air box.
Could it be you need to check your air filter or MAF sensor wires? Are there any codes that show up periodically on the DIC that might indicate problems?
I'm at 5,200 ft altitude and have been using only CHEVRON fuel. I drive my car only on weekends and generally take 100-125 mile round trips through the mountains to 7,000 ft altitude with some very challenging twisties and cut backs in northern AZ. I never average less than 20.5 mpg on the DIC and by hand computations, it's usually 20.1 to 20.3 mpg at the lowest. My car is also stock with the exception of a K&N drop in filter in a modified Z06 air box.
Could it be you need to check your air filter or MAF sensor wires? Are there any codes that show up periodically on the DIC that might indicate problems?
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Le Mans Master
Joined: Dec 2000
Posts: 9,900
Likes: 1,841
From: Hot Springs AR
E10 is now quite prevalent across the nation (much to the delight of the corn growers). I have found a few stations in my area that claim they don't run E10 in their pumps, and my mileage tends to back up that claim. So, you might want to ask your neighborhood stations if they know or not.
Another welcome to PC world (and no, not the magazine).
Mike
Melting Slicks
Joined: Sep 2006
Posts: 2,736
Likes: 7
From: Redding CA
How many actual miles are you guys getting out of your tanks?? A4 tranny?
I just checked mine, I went 1/2 tank highway(exactly) then 1/2 tank around town. I set the cruise at 125 for about 20 miles at 3300ish RPM on the highway 1/2 tank and got on it maybe 4 times through the "around town 1/2 tank). The car went about 335 miles on a tank.
Mine's a 2000 A4.
Thx,
DZ
I just checked mine, I went 1/2 tank highway(exactly) then 1/2 tank around town. I set the cruise at 125 for about 20 miles at 3300ish RPM on the highway 1/2 tank and got on it maybe 4 times through the "around town 1/2 tank). The car went about 335 miles on a tank.
Mine's a 2000 A4.
Thx,
DZ
Tech Contributor
Joined: Sep 2005
Posts: 1,731
Likes: 82
From: New Market AL
My daily commute is ~ 100 miles, with roughly ½ being interstate, ¼ country 2-lane, and ¼ city. I routinely get 450+ miles out of a tank of gas. My calculated average is usually 28 mpg. My car is a '99 M6 with Vararam, LT, x-pipe, Borla Stingers. I am not sure what the new cam will do though...
Burning Brakes
Joined: Nov 2002
Posts: 807
Likes: 21
From: Los Altos CA
My results are consistent with a lot of the people on this post. My DIC reading is about 8% higher than the actual mileage. About half my driving is on the freeway and half in town with traffic lights (no really heavy stop and go stuff) I get 19-19.5 mpg. I have an '00 A4
Pro
Joined: Feb 2006
Posts: 647
Likes: 2
From: Keystone, I.T.
I've had only one vehicle that actually got better mileage than the trip computer indicates and that's my '01 Dodge diesel truck. The Vette always gets less that the computer indicates. I always use quality premium fuels, Conoco/Phillips, Texaco or Shell. I've got an '02 vert with automatic, 3.15 gears, no performance mods and 80,000 miles on the clock. I drive it 14 miles to work a couple of times a week and longer trips on the weekends. I have never gotten less than 22 mpg. On long road trips running 70 mph it will get 28 mpg. These are pencil and paper figures based on actual mileage devided by actual gallons of fuel used. I don't know if thats good or bad but I am very satisfied with this aspect of the cars performance. 
Last edited by widewheel; Nov 7, 2007 at 08:37 PM.
Melting Slicks
Joined: Sep 2006
Posts: 2,736
Likes: 7
From: Redding CA
http://www.zip-products.com/Corvette...sp?dept_id=342
Accessories
Alright cool, I'm around 19-20 myself.
Thx,
DZ
Accessories
Alright cool, I'm around 19-20 myself.
Thx,
DZ
Drifting
Joined: Dec 2005
Posts: 1,720
Likes: 3
From: East Hampton CT
I'm sure everyone knows, but you need to use the same pump back to back when computing the fuel that was consumed, otherwise you could be as much as a gallon off either way that can screw up your calculations. Here in CT there is a Hess near my house that tilts your car on a pretty good angle while filling for most of the pumps...if you fill up there and then use any other flat station, you'll get some REALLY good (or bad) numbers that will confuse you for a bit.
Melting Slicks
Joined: Jan 2004
Posts: 3,012
Likes: 15
From: Jensen Beach FL
B3501 using EFI Live is called "scaler for fuel economy output". Mine is set to 1 but I'm sure you can do a .98 or 1.02 (EFI Limits a min of 0 and max of 2) to get your DIC matching your hand calculations.
I'm sure everyone knows, but you need to use the same pump back to back when computing the fuel that was consumed, otherwise you could be as much as a gallon off either way that can screw up your calculations. Here in CT there is a Hess near my house that tilts your car on a pretty good angle while filling for most of the pumps...if you fill up there and then use any other flat station, you'll get some REALLY good (or bad) numbers that will confuse you for a bit.
I'm sure everyone knows, but you need to use the same pump back to back when computing the fuel that was consumed, otherwise you could be as much as a gallon off either way that can screw up your calculations. Here in CT there is a Hess near my house that tilts your car on a pretty good angle while filling for most of the pumps...if you fill up there and then use any other flat station, you'll get some REALLY good (or bad) numbers that will confuse you for a bit.
