I have a '96 i30 and am just starting to watch my mileage more acurately. I drive mostly freeway miles and on my last tank (with typical driving behavior) got about 22.7 mpg. Is that about right (as in ballpark) for what I should be getting??
:help
car has 112k on it for what its worth...
mileage question
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Q45tech
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- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Average mileage is a factor of average rpm plus what ever percentage is wasted in acceleration.
A gallon of gasoline is not a precise number because different blends weigh different amounts.......within 2-3% usually.If you are using oxygenated fuels the mileage will be 3-4-5% less due to the lower heat value of the gasoline. Plus O2 sensor are calibrated for non oxygenated so the errors created could subtract another 1-2%.
ODB2 models are much more sensitive to the perfect operating condition of the O2 sensors. Therefore short of extensive testing they should probably all be replaced every 60-70,000 miles to squeeze the last drop of MPG.
Multivalve V6 need to run at 10-15% higher rpms [compared to multivalve V8] to develop enough torque to maintain steady smooth low load cruise. This has the effect of making the fuel consumption 10-15% higher. Think of your 3.0 liter as a 3.3-3.5 liter as far as gasoline consumption is concerned at least at cruise. ...........GM old fashioned 3.8 2 valve V6 can function at a much lower rpm [lower than a Q V8].....say 1850 rpm vs 2000 vs 2300 rpm [your I30] at the same highway speed in the same weight car [same drive train] ............so it has the fuel consumption of a 3.0 liter..........but doesn't generate anywhere near the high rpm power of your I30........and the 3.8 consumes more at idle than your 3.0 liter.
Owners don't realize tha EPA test proceedures assume a 55 mph average speed and very light acceleration plus no AC conducted in 70F weather with the tires and alignmnt perfect.
MPG hides the intantaneous effects of averaging, a better method is pounds per hour of fuel use.
There is a lot of difference between using 14.53 pounds per hour in averaging 55 mph and 18.50 pounds per hour averaging 70 mph.............as the amount of fuel you use per unit of time is directly related to rpm........until you reach say 71-75-80 mph where the fuel economy program starts to be disregarded ......extra fuel is pushed in to cool the combustion chambers so the linear relationship starts to diverge.
Based on engine size corrected for rpm and weight at a prudent average speed say 65 mph I would calculate 26 mpg AC off, 24 mpg ac on.
A gallon of gasoline is not a precise number because different blends weigh different amounts.......within 2-3% usually.If you are using oxygenated fuels the mileage will be 3-4-5% less due to the lower heat value of the gasoline. Plus O2 sensor are calibrated for non oxygenated so the errors created could subtract another 1-2%.
ODB2 models are much more sensitive to the perfect operating condition of the O2 sensors. Therefore short of extensive testing they should probably all be replaced every 60-70,000 miles to squeeze the last drop of MPG.
Multivalve V6 need to run at 10-15% higher rpms [compared to multivalve V8] to develop enough torque to maintain steady smooth low load cruise. This has the effect of making the fuel consumption 10-15% higher. Think of your 3.0 liter as a 3.3-3.5 liter as far as gasoline consumption is concerned at least at cruise. ...........GM old fashioned 3.8 2 valve V6 can function at a much lower rpm [lower than a Q V8].....say 1850 rpm vs 2000 vs 2300 rpm [your I30] at the same highway speed in the same weight car [same drive train] ............so it has the fuel consumption of a 3.0 liter..........but doesn't generate anywhere near the high rpm power of your I30........and the 3.8 consumes more at idle than your 3.0 liter.
Owners don't realize tha EPA test proceedures assume a 55 mph average speed and very light acceleration plus no AC conducted in 70F weather with the tires and alignmnt perfect.
MPG hides the intantaneous effects of averaging, a better method is pounds per hour of fuel use.
There is a lot of difference between using 14.53 pounds per hour in averaging 55 mph and 18.50 pounds per hour averaging 70 mph.............as the amount of fuel you use per unit of time is directly related to rpm........until you reach say 71-75-80 mph where the fuel economy program starts to be disregarded ......extra fuel is pushed in to cool the combustion chambers so the linear relationship starts to diverge.
Based on engine size corrected for rpm and weight at a prudent average speed say 65 mph I would calculate 26 mpg AC off, 24 mpg ac on.
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i30daretodif
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Jeff Williams
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