Civic Hatchback Aerodynamics part deux

[XFi]

Wow, NICE! I wonder who is going to carry Team OPEC Busters numbers this round of the competition?

[ajohnmeyer]

So I got the rear fairings finished up and installed. They need a little bit more coaxing with the heat gun in places. That and the heads of the bolts and the washers need a good coat of white paint.








For all those interested in using ABS in the future please note that it will discolor if you heat it up too much with the heat gun, so heat up the back side of the piece so you wont see the discoloration when it is installed.

[cfg83]

ajohnmeyer, aka "Surly" -

Verrrrrrrrry Nice.

CarloSW2

[ajohnmeyer]

So today was my first day driving with the rear fairings installed. I'd guesstimate that I'm seeing a 7-10% improvement in coast-down. My passenger side fairing is a little rattly, the plastic is occasionally rattling against the aluminum support, nothing a little bending or velcro can't handle.

And all of this has got me thinking about what to do next. I think I'll have enough ABS to do the front fairings, grill block and a front undertray (bumper to front suspension arms.) I'm not so worried about saving enough ABS for the undertray because I can get tons of coroplast from my work for free if I need it. We have tons and tons of big outdoor Pepsi sinage that's all printed on white coroplast, and it all gets thrown away within about 6 months of being put up.

I've been thinking a lot about how to do the front fairings, my very first idea was to make something based on those snap-on "spinner" hubcaps. If the fairing could be attached to the outer "spinner" portion of the hubcap, then it could in theory pivot with the wheel when it is turned. This idea got shot all to hell when I made a template of the front wheel and discovered that the wheel well is slightly assymetrical, I think that would make for some problems.

Other options as I see them are conveyor rollers as per basjoos's fairings or using some teflon sheet, I think someone mentioned that in COZX2's fairing thread. So far finding the small rollers seems to be a problem and I wonder how they will hold up to rain/snow/salt/etc.

Opinions anyone?

[cfg83]

ajohnmeyer -

Originally Posted by ajohnmeyer

...

I've been thinking a lot about how to do the front fairings, my very first idea was to make something based on those snap-on "spinner" hubcaps. If the fairing could be attached to the outer "spinner" portion of the hubcap, then it could in theory pivot with the wheel when it is turned. This idea got shot all to hell when I made a template of the front wheel and discovered that the wheel well is slightly assymetrical, I think that would make for some problems.

...

Opinions anyone?

On Taxis, there are "add caps" that maintain their orientation.

They not spinnin': ads on taxi cab hubcaps
http://www.engadget.com/2004/09/13/t...i-cab-hubcaps/

Taxi Advertising
http://www.nationaltransitmedia.com/...tising/ppc.php

TrafficAds
http://www.weekendtoys.com/catagorie...rafficads.html

HubAds ? The Wheels of Advertising
http://www.adsoncars.com/hubads.asp

NOT SPINS - NOT ROTATING - STAY STILL
http://www.autopure.com/NotSpins.htm
Attachment 1087
Attachment 1088

They are not static, they "rock" back and forth when the car changes speed because a weight to keep the add oriented.

You wouldn't be able to make a perfect closure because of the asymmetry you mention, but it would be close.

CarloSW2

[basjoos]

Originally Posted by ajohnmeyer

Other options as I see them are conveyor rollers as per basjoos's fairings or using some teflon sheet, I think someone mentioned that in COZX2's fairing thread. So far finding the small rollers seems to be a problem and I wonder how they will hold up to rain/snow/salt/etc.

Opinions anyone?

I got my conveyer rollers from McMaster Carr (Part # 2278T11)
3/4" Diameter X 4-7/8" long, $8.71 each. I've been using them since last summer (put about 40,000 miles of them so far) and haven't had any problems with snow or salt during my usual commute into the Asheville NC area. The only maintenance I do on them is to add a drop of oil to the end bearing every couple of months. Since I exhaust my hot radiator air out through my front wheel wells, the wells stay warm, and dry out quickly once I park or reach dry road surfaces.

[ajohnmeyer]

After thinking a lot about the "spinner"-based front fairing design, I've decided that it's more trouble than it's worth. The primary problem with that design is allowing for the up-and-down suspension movement.

Sometime this week I'm going to fit up some cardboard templates for the front fairings just to see what kind of clearances that I have to work around.

So far I'm liking the teflon (PTFE) idea because of the potentially lower profile and overall KISS factor.