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aerohead · 03-26-2011, 05:31 PM

Your beetles Cd should be more like 0.50 rather than 0.41.
The 1934 Chrysler Airflow had essentially the same drag coefficient.
With a bellypan,bumper delete,flush glass,raked nose,blended fenders and semi-decagonal panoramic windshield they aero-modded the car down to Cd 0.373.
Next,by bulking in the body void over the beaver tail,up close to the Template line,and chopped off vertical just like Fachsenfeld and Kamm recommended later,the drag dropped to Cd 0.32.
A 36" stinger boat tail was added finally for Cd 0.244.
For you to go to Cd 0.18 you'd need to stay right on the Template and extend the tail a bit further.
I've never seen a Beetle do better than 28 at real highway speeds.The Karmann Ghia( Cd 0.39 and approx 18.5 sq ft frontal area) body will produce 40 mpg on the same chassis wityh zero powertrain mods.

03-26-2011, 05:31 PM	#41 (permalink)
aerohead Master EcoModder Join Date: Jan 2008 Location: Sanger,Texas,U.S.A. Posts: 16,267 Thanks: 24,392 Thanked 7,360 Times in 4,760 Posts	bug Your beetles Cd should be more like 0.50 rather than 0.41. The 1934 Chrysler Airflow had essentially the same drag coefficient. With a bellypan,bumper delete,flush glass,raked nose,blended fenders and semi-decagonal panoramic windshield they aero-modded the car down to Cd 0.373. Next,by bulking in the body void over the beaver tail,up close to the Template line,and chopped off vertical just like Fachsenfeld and Kamm recommended later,the drag dropped to Cd 0.32. A 36" stinger boat tail was added finally for Cd 0.244. For you to go to Cd 0.18 you'd need to stay right on the Template and extend the tail a bit further. I've never seen a Beetle do better than 28 at real highway speeds.The Karmann Ghia( Cd 0.39 and approx 18.5 sq ft frontal area) body will produce 40 mpg on the same chassis wityh zero powertrain mods.