Aero mods for our coupes??

[Sayyad]

From what I've read the coupe or sedan or one with a trunk tends to have a better coefficient of drag than the same car with a wagon back or a hatch. This is true for Volkswagens at least.
Airflow seems to separate across the whole back of a hatch. The flow usually either detaches from the rear window of a sedan and then reattaches at the tail end of the trunk or stays attached to the rear window all the way from the roof to the tail end of the trunk, thus resulting in a smaller wake.
The wagon or hatchback has a wake that's most of the height and width of the car itself, whereas the sedan should only have a wake that's most of the width of the car but only about half the height.

[aerohead]

Originally Posted by smwoodruff0908

So I've been reading a lot on the forums, and I love what I've been seeing. I'm now sporting 2 EcoModder.com stickers, too! One thing I've been wondering is, where is all the aero mods for coupes? I drive a 2000 Civic DX coupe, and love the idea of the Kammback, boat tails, etc. but I can't find any information on how to make a coupe more aerodynamic. So what do you guys think? What kind of mods can we coupe guys do to our rears to get better FE? Also, if you have any tips/info pertaining specifically to Civic coupes, I'd love to hear Thank you all very much!

-Woody

Woody,look at Cd's posts,and notice the windtunnel photograph of the little Opel,or whatever that car is.The smoke defines the path the air wants to follow.You need to shape the roofline and back of your car as you see in Cd's little photo.Look also at Cd's photoshopped car,also basjoos',and Andrew's Civics,or my old CRX.MetoMPG's permanent Kammback thread also has an aerodynamic template you can use to design your mods.Read through the posts,it's self-explanatory.

[i_am_socket]

I don't suppose I'm the only one that initially read the thread title as "Aero mods for couples"?

[swoody]

Thanks for all the helpful info guys I've seen that aero shape in Cd's pic before, and have gotten the gist of the whole concept, but I wanted to see if anyone has already done something to a coupe rearend, or what ideas people had about it.

Originally Posted by i_am_socket

I don't suppose I'm the only one that initially read the thread title as "Aero mods for couples"?

hahaha No, I think acquiring a more "aerodynamic shape" for couples would be for the "Adults Only" EcoModder forum
Riding the ridges?
Hopefully no forced Auto-Stop!
High-Speed Pulse and Glide?
Face-out Parking? (that's a strange one )
Driving with load??

OK OK!! I've got a sick mind... haha... I'll stop
"And now for something completely different"

[Sayyad]

Would those be aero mods for efficiency or for speed? Maybe downforce? Perhaps more lift wouldn't be a bad thing either
I'm playing with my Jetta's side profile in Photoshop and I've noticed one significant potential advantage that hatchbacks have over coupes with regards to aero modding. It seems like it is much easier to build and attach a boat tail to a hatchback. Having a trunk which does not naturally taper inwards at a 15 degrees gets in the way. It may be possible to build a boat tail hanging off the back of the trunk but otherwise I don't see any good way to boat tail a sedan, apart from extensive cutting and welding of the trunk itself and reorganizing the rear windshield support for a better angle.
Still, the Aptera is wide and rectangular right to the back edge, but it gets flatter as it approaches the tail lights and license plate.
It might be as simple as a flat spoiler over the rear edge of the trunk like the Ford 999 land speed racer. That should give the airflow lots of space to reattach and the flat, sharp rear edge should make for a clean final separation for a smaller wake than a normal rounded trunk lid edge.