Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - help me with aerodynamics in my Chevrolet Blazer truck

aerohead · 11-19-2011, 02:53 PM

Here are some data on the Blazer:
* The Cd for the pickup on which the K5 is based is 0.535.The K5 will be higher due to exposed underbelly,wider tires,etc..
* The frontal area is 34.3-square feet
* CdA will be above 18.35-square feet
* Road Load 'dynamometer' @ 50 mph = 19.9 horsepower ( front axle not measured)
* Actual road load @ 50 mph approx. 24.142-horsepower
* Engine load @ 50 mph approx. 26.824 brake horsepower
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* 1974 C10 pickup @ 55-mph steady,with 250 cu in 6-cyl,4-speed manual,and 3:07 rear axle = 17.7 mpg.
* same truck,with softened hood leading edge,front airdam,and tonneau cover = 18.6 mpg.
* 1982 C10 w/ 6.2-liter Diesel 2WD = 31 mpg EPA HWY
* 1982 C10 w/ 6.2-liter Diesel 4WD = 29 mpg EPA HWY
* 1982 C10 --------------------- = 19 mpg EPA HWY
* 1986 C10,350 cu in V-8,Turbo-hydramatic w/ lockup,mild cam,performance intakemanifold,275X 60R-15 tires = 20 mpg @ 65 mph
* 1987 C1500, Cd 0.45,31.899-square feet Af (est), VORTEC V-6,M-5,@ 65 mph,with air conditioning and 1/2-tonneau cover = 23 mpg
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If you are very attached to the Blazer,anything you do to mimic the form of contemporary pickups and SUVs will pay you savings at the pump.
* JEEP has gone to air suspension on the new Grand Cherokee to lower it on the HWY.
* You see how all the 'noses' of current vehicles have been rounded.
* Drip edges have been eliminated
* Windshields and glass is more flush to the body
* The sides of the body are flush with the wheels,or vice versa
* Wheels are more 'enclosed' either as a wheel or with wheelcover
* Fenders and hoods slope downward
* Bellys are smoothed
*Airdams scoot the air over and around the vehicle
*Electric fans replace engine-driven units
*Grilles are blocked to restrict the amount of airflow through the cooling system
*Vehicles are 'longer' in relation to their height
*Rooflines are now mimicking the early Hungarian and German low drag forms of the 1920s-30s.
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The Blazer should respond very well to streamlining,however,since it is a carb'd engine,it's fuel metering system and BSFC will be more affected than fuel-injected vehicles.

11-19-2011, 02:53 PM	#15 (permalink)
aerohead Master EcoModder Join Date: Jan 2008 Location: Sanger,Texas,U.S.A. Posts: 16,268 Thanks: 24,393 Thanked 7,360 Times in 4,760 Posts	some K5 Blazer specs Here are some data on the Blazer: * The Cd for the pickup on which the K5 is based is 0.535.The K5 will be higher due to exposed underbelly,wider tires,etc.. * The frontal area is 34.3-square feet * CdA will be above 18.35-square feet * Road Load 'dynamometer' @ 50 mph = 19.9 horsepower ( front axle not measured) * Actual road load @ 50 mph approx. 24.142-horsepower * Engine load @ 50 mph approx. 26.824 brake horsepower ---------------------------------------------------------------------------- * 1974 C10 pickup @ 55-mph steady,with 250 cu in 6-cyl,4-speed manual,and 3:07 rear axle = 17.7 mpg. * same truck,with softened hood leading edge,front airdam,and tonneau cover = 18.6 mpg. * 1982 C10 w/ 6.2-liter Diesel 2WD = 31 mpg EPA HWY * 1982 C10 w/ 6.2-liter Diesel 4WD = 29 mpg EPA HWY * 1982 C10 --------------------- = 19 mpg EPA HWY * 1986 C10,350 cu in V-8,Turbo-hydramatic w/ lockup,mild cam,performance intakemanifold,275X 60R-15 tires = 20 mpg @ 65 mph * 1987 C1500, Cd 0.45,31.899-square feet Af (est), VORTEC V-6,M-5,@ 65 mph,with air conditioning and 1/2-tonneau cover = 23 mpg -------------------------------------------------------------------------- If you are very attached to the Blazer,anything you do to mimic the form of contemporary pickups and SUVs will pay you savings at the pump. * JEEP has gone to air suspension on the new Grand Cherokee to lower it on the HWY. * You see how all the 'noses' of current vehicles have been rounded. * Drip edges have been eliminated * Windshields and glass is more flush to the body * The sides of the body are flush with the wheels,or vice versa * Wheels are more 'enclosed' either as a wheel or with wheelcover * Fenders and hoods slope downward * Bellys are smoothed Airdams scoot the air over and around the vehicle Electric fans replace engine-driven units Grilles are blocked to restrict the amount of airflow through the cooling system Vehicles are 'longer' in relation to their height *Rooflines are now mimicking the early Hungarian and German low drag forms of the 1920s-30s. ------------------------------------------------------------------------- The Blazer should respond very well to streamlining,however,since it is a carb'd engine,it's fuel metering system and BSFC will be more affected than fuel-injected vehicles.