How much MPG loss going from 2.73's to 3.73's?
10-13-2002, 10:33 AM
#1
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How much MPG loss going from 2.73's to 3.73's?
How much MPG loss going from 2.73's to 3.73's?
Car averages 24-25mpg daily driving.
Car averages 28-30mpg on highway.
Best highway mpg was 32.5mpg
What mpg should I expect if I go from 2.73's to a 3.73 Auburn posi?
Details are I have a 4th Gen TCS rear end I can't use in my 99 T/A because the 99 T/A doesnt have TCS.
Thoughts?
Thanks
Car averages 24-25mpg daily driving.
Car averages 28-30mpg on highway.
Best highway mpg was 32.5mpg
What mpg should I expect if I go from 2.73's to a 3.73 Auburn posi?
Details are I have a 4th Gen TCS rear end I can't use in my 99 T/A because the 99 T/A doesnt have TCS.
Thoughts?
Thanks
10-14-2002, 11:40 PM
#3
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Car: 86 Firebird
Engine: 355 4 bbl
Transmission: TKO 600
Axle/Gears: 3.73 L/S
You might want to factor in a deduction in fuel economy of about 5 - 10% "hooligan losses" due to the additional enjoyment of footing the throttle.
10-15-2002, 12:17 AM
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Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
It will depend somewhat on your cam, I didn't lose any mileage at all going from 2.73 to 3.54 because my cam is happier with a higher cruising RPM.
10-15-2002, 01:07 PM
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Car: 1984 Firebird
Engine: 350 Terminator EFI
Transmission: T56
Axle/Gears: 4.10
i went from 3.23 to 3.73, its a smaller jump but i also noticed a minimal decrease in mileage, when i am just driving. in a hard running situation its noticably worse, due to the secondaries opening, as with Apeiron my cam prefers a higher cruise rpm
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