Fuel mileage question
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Fuel mileage question
How is the fuel mileage in the DIC calculated? Is it based on algorithmic calculations based on engine speed, injector pulse, air flow, etc , so it's a math determination, or is it based on actual fuel flow?
I was asking because my car is modified, ProCharger, 60# injectors, hedders, etc., and I was wondering if the fuel mileage was accurate.
Yes, I'm too lazy to do it the old fashion way!
I was asking because my car is modified, ProCharger, 60# injectors, hedders, etc., and I was wondering if the fuel mileage was accurate.
Yes, I'm too lazy to do it the old fashion way!
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
What kind of tune do you have in the car? Are you basing the tune on the normal .75 Litre cylinder volume or are you using a proportional tune? If the .75, then the numbers are probably pretty close.
See, ask a question, get a question!
Elmer
See, ask a question, get a question!
Elmer
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Elmer,
I really don't know. The car was initially tuned by sending the ECM off to the ProCharger tuner upon initial installation, then once everything was installed, I drove the car to a local shop where a fairly conservative tune was installed. The car makes 550 rwhp, whereas I've seen cars with the same specifications as mine putting down 600+, so I know there is more in the engine, but honestly, the car is scary fast the way it currently is configured, so I probably will not seek additional power. But, not sure the basics of the tune. Not in my area of expertise.
I was just curious about the mpg accuracy.
I really don't know. The car was initially tuned by sending the ECM off to the ProCharger tuner upon initial installation, then once everything was installed, I drove the car to a local shop where a fairly conservative tune was installed. The car makes 550 rwhp, whereas I've seen cars with the same specifications as mine putting down 600+, so I know there is more in the engine, but honestly, the car is scary fast the way it currently is configured, so I probably will not seek additional power. But, not sure the basics of the tune. Not in my area of expertise.
I was just curious about the mpg accuracy.
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
2015 C7 of the Year Finalist
The reason I asked is that the E-Force SC I installed came with a tune. The tune was a proportional tune due to the limitations of the LS2 MAF and ECM. Basically, they had to lie to make it work. Well, the lie changes the cylinder volume and the "Mileage remaining" went nucking futz. I was getting 40+ instant MPG and 5-600 miles left in the tank. Sure, I believed that crap.
So, the tuner reloaded the stock tune and then tweaked the files as needed to make it work. I now get 28-29 on the highway and the miles in the tank are accurate. I really can get the 400 miles left in the tank easy.
So, What do you have? LS1? It should be ok and if the numbers on the instant MPG look reasonable, then the remaining in the tank numbers should be fine too. I'd guess that the ECM calculates via math the mileage as it knows everything going on in the engine as far as air & fuel flow.
Elmer
So, the tuner reloaded the stock tune and then tweaked the files as needed to make it work. I now get 28-29 on the highway and the miles in the tank are accurate. I really can get the 400 miles left in the tank easy.
So, What do you have? LS1? It should be ok and if the numbers on the instant MPG look reasonable, then the remaining in the tank numbers should be fine too. I'd guess that the ECM calculates via math the mileage as it knows everything going on in the engine as far as air & fuel flow.
Elmer
Last edited by eboggs_jkvl; Apr 29, 2013 at 09:31 AM.
