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drmiller100 · 04-09-2012, 12:13 AM

so been doing some measuring, bought some parts, will start fabbing this week.

back of my suburban is roughly 4 feet tall and 6 feet wide.

I'm going to make a back of the car with 4 foot long sides (slightly less then 4 feet long).

so, top will be 1:3 drop ratio - about 19 degrees. Sides I think i will do the same.
Bottom willl be 1:4 rise - about 15 degrees.

my math says the suburban has a 3456 square inches of "frontal area" in the back, and the new "frontal area" will be 800.

any math to guess what reduction in drag will be? math? Found some info on the net which suggests the suburban is a .5 Cd, so there is some room for improvement.

04-09-2012, 12:13 AM	#18 (permalink)
drmiller100 Master EcoModder Join Date: Dec 2011 Location: Boise Idaho Posts: 842 Thanks: 39 Thanked 89 Times in 69 Posts	so been doing some measuring, bought some parts, will start fabbing this week. back of my suburban is roughly 4 feet tall and 6 feet wide. I'm going to make a back of the car with 4 foot long sides (slightly less then 4 feet long). so, top will be 1:3 drop ratio - about 19 degrees. Sides I think i will do the same. Bottom willl be 1:4 rise - about 15 degrees. my math says the suburban has a 3456 square inches of "frontal area" in the back, and the new "frontal area" will be 800. any math to guess what reduction in drag will be? math? Found some info on the net which suggests the suburban is a .5 Cd, so there is some room for improvement.