Effectiveness of side skirts?

[aerohead]

The only thing I have "scientific" for side skirts is from the development of the 1982 Pontiac Trans Am.--------- The skirts provided a 4.4% drag reduction.------------ When combined with the under-car wrap-around front airdam,drag was reduced 7%,which would yield a 3.5% improvement in mpg at 55-mph.

[rollercoaster]

Originally Posted by aerohead

The only thing I have "scientific" for side skirts is from the development of the 1982 Pontiac Trans Am.--------- The skirts provided a 4.4% drag reduction.------------ When combined with the under-car wrap-around front airdam,drag was reduced 7%,which would yield a 3.5% improvement in mpg at 55-mph.

Dodge did this back in the late 80's too.

[aerohead]

Best I can tell, the SAE still recommends :
1) a 16- degree 'approach' angle ahead of the front tires.
2) 10-degree 'breakover' angles behind the front tires, and ahead of the rear tires.
3) 10-degree 'departure' angle behind the rear tires.
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4) If these angles are not respected, you run the risk of a ground strike and body damage.
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5) 'Active' airdams were introduced in the early 70s by VOLVO on their VCC concept, and would be a 'workaround' for the front clearance.
6) 'Active' diffusers were introduced by GM in 1982 ( Aero 2000/ EPCOT concept ), and would be a 'workaround' for the rear.
7 If you're willing to take all driveway ramps at an oblique angle, you might be able to survive with a 'cheater' set of skirts or wheel fairings.
The 'template' illustrates a wheel fairing package ( or skirts ) which respects all SAE underbody clearance requirements.
PS, rubber belting would be able to survive ground strike and abrasion, although it would be subject to aeroelastic deformation.
PS-2 In the State of California, expect the Highway Patrol to pull you over if they see any part of your car lower than the bottom of the wheel rim.

[Tahoe_Hybrid]

Originally Posted by aerohead

Best I can tell, the SAE still recommends :
1) a 16- degree 'approach' angle ahead of the front tires.
2) 10-degree 'breakover' angles behind the front tires, and ahead of the rear tires.
3) 10-degree 'departure' angle behind the rear tires.
--------------------------------------------------------------------------------------
4) If these angles are not respected, you run the risk of a ground strike and body damage.
-------------------------------------------------------------------------------------
5) 'Active' airdams were introduced in the early 70s by VOLVO on their VCC concept, and would be a 'workaround' for the front clearance.
6) 'Active' diffusers were introduced by GM in 1982 ( Aero 2000/ EPCOT concept ), and would be a 'workaround' for the rear.
7 If you're willing to take all driveway ramps at an oblique angle, you might be able to survive with a 'cheater' set of skirts or wheel fairings.
The 'template' illustrates a wheel fairing package ( or skirts ) which respects all SAE underbody clearance requirements.
PS, rubber belting would be able to survive ground strike and abrasion, although it would be subject to aeroelastic deformation.
PS-2 In the State of California, expect the Highway Patrol to pull you over if they see any part of your car lower than the bottom of the wheel rim.

buy a bigger rim then

[cRiPpLe_rOoStEr]

I remember side skirts were quite usual in the '90s as part of aerodynamic kits, even though people simply bought them because of the "go-fast look". Once in a while I still see some Opel Corsa B with side skirts and a rear spoiler.