Thread: wake reduction
View Single Post
Old 04-23-2010, 07:25 PM   #10 (permalink)
aerohead
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 16,312
Thanks: 24,439
Thanked 7,386 Times in 4,783 Posts
Mercedes 190E 2.5 EVO II

Quote:
Originally Posted by laack View Post
I ran some quick numbers just to see what my options might be.
  • if i try to match the template, I would need to extend my tail end about 19 inches. I'm sure someone around here would rip that off to tighten up their parallel park job.. cant do it.
  • If i extend it just 10" it would be 12 degrees slope, as previously recommended, from trailing edge to leading edge of rear windshield.
  • the glass slope down is 22 degrees
  • slope from leading edge of glass to trailing end of trunk is 14 degrees

disclaimer- this assumes that all my measurements and calculations were accurate. inconsistent measurements forced me to take an average of height and length from top of glass to point equal to top of trunk then from that point to the end of the trunk.

random thoughts/options at this point- I remember an older thread on here posting VG results including a youtube link. promising tuft testing but disappointing results. no change in mpg. rough experiment but not enticing enough for me to waste my time on that alone.
extend a piece coroplast back 11 inches-I'm not fully convinced that that will actually reduce my wake or smooth the transition of separated airflow at all. This plus VGs. out of curiosities sake i may do it just for the tuft test a couple of coast down tests.
attach an up-swept spoiler- in terms of drag reduction it seems counter productive but i do understand that it makes the air's path a little longer & gentler. I'm not willing to rule it out yet, but is there any data associated with how much improvement it can yield.

Any other thoughts?

later plans are grille block and rear wheel covers. rust is an issue on the rear wheel covers though so i'm still trying to figure out how to attach it w/o drilling into visible portions of the bumper. I also want to hook up an led to the rad. fan so i know when its on.
Laack,GOOGLE the Mercedes above in the title box and see what they did.
  Reply With Quote