Gas milage

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Mar 25, 2007 | 02:10 AM

vettegator005

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Melting Slicks

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From: Longmont Colorado

Gas milage

I have a 99 c5 6-speed with patriot stage 2 heads, a comp cam with .571 lift and full exhaust. What kind of gas milage would i get on the interstate?

Mar 25, 2007 | 02:17 AM

DeeGee

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From: Horncastle Lincolnshire, England

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I suspect theres only one way to find that out. Treat yourself and hit the freeway.

Don't forget to hit reset on the trip meter on the DIC when you start the check otherwise you get average data over the last few months.

Mar 25, 2007 | 02:41 AM

FactoryRaceCar

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Quote:

Originally Posted by DeeGee

I suspect theres only one way to find that out. Treat yourself and hit the freeway.

Don't forget to hit reset on the trip meter on the DIC when you start the check otherwise you get average data over the last few months.

Mar 25, 2007 | 09:30 AM

Vetteman Jack

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Have no idea what the gas mileage may be, but the car will be a lot of fun to drive.

Mar 25, 2007 | 10:07 AM

C5XTASY

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From: Monticello MN

Quote:

Originally Posted by vettegator005

I have a 99 c5 6-speed with patriot stage 2 heads, a comp cam with .571 lift and full exhaust. What kind of gas milage would i get on the interstate?

If you changed injectors to 28.8lbs, or higher, (1999 & 2000s had the smaller 26.2 lb injectors) and the computer calculational data base wasn't changed to recognize that, you will get a falsely high reading on the DIC. A/F ratio can be adjusted and everything else adjusted, but, in addition, the calculational data base must also be updated for anywhere near an accurate mpg readout. This isn't always done during an LS1EDIT tune. Not a big deal, but just a FYI.
Ed

Mar 25, 2007 | 10:14 AM

C5XTASY

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From: Monticello MN

Quote:

Originally Posted by DeeGee

I suspect theres only one way to find that out. Treat yourself and hit the freeway.

Don't forget to hit reset on the trip meter on the DIC when you start the check otherwise you get average data over the last few months.

Are you sayin that the "average mpg" readout will be erroneous if the trip meter isn't reset? Or, are you saying that average mpg readout will be erroneous if the "average mpg" meter isn't reset? If it's the former, I didn't realize that the displayed trip meter readout had an input into the "average mpg" calc readout.

Mar 25, 2007 | 10:17 AM

TopFuelTim

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From: Cumming Georgia

I appreciate that info

Quote:

Originally Posted by C5XTASY

Thank you!! The injectors were changed to 28.8lbs on my 2000 by the previous owner, and the DIC is about 10% optimistic when it comes to gas mileage. Your post explains why. My mpg is still very good, got 24mpg out of my last tank (and DIC indicated 27.0mpg).

Tim Glover

Mar 25, 2007 | 10:22 AM

Vega$Vette

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From: Wesley Chapel, FL Las Vegas, NV

I have Patriot Stage IIs, .575 lift, 3:42s with an A4 and still get about 28 mpg highway at 75-80 mph.

But then again I really don't care about mileage.