5th generation civic hatchback - improving aerodynamics

[AndrewJ]

[MetroMPG]

That is so funny. I laughed. Thanks.

PS - don't try to cook the pizza on the plastic wheel cover. It only works the other way around.

[SVOboy]

Oooh! I get it now.

[AndrewJ]

So I started on this bit last week, but never got around to posting about it.
I figured that some skirts with integrated wheel spoiler-type-things would be a good next step.

Lucky for me, Honda already put some lovely side-skirts on my car about 13 years ago!





Now, unfortunately they're not exactly doing me any aerodynamic favors in their current configuration. Nothing a heat gun can't fix though.
Simply remove the fasteners from the bottom, heat and bend.

[SVOboy]

Haha, I would never have expected that,

Did you prop up the back at all in order to hold stuff in position?

[AndrewJ]

No, not yet, and I only have one side done. I don't know what kind of plastic that it's made out of but it takes a LOT of heat to soften it up sufficiently, and it smells bad when it's heated up.

But anyway, I need to maybe put a piece of 1" x 1/8" aluminum behind it to hold it straight. That, and I'll be making little wheel spoilers/boattail things to go on either end. I figure the combination of the two will support it quite nicely.

[SVOboy]

I'm pretty sure it's some kind of PCV. Prolly getting cancer from the fumes,

I wonder if any old generic honda body kit skirts would work for this purpose...

[basjoos]

I heated up and bent a 90 degree into a piece of coroplast and screwed it onto the underside of that black plastic piece. The coroplast is flexible enough to bend out of the way when contacting the road surface (easy enough to do when carrying a heavy load in the back) and can easily be replaced if/when its gets eroded down too far by occasional scrubbing with the road's surface. The back portion of the side skirt especially tends to scrub the road when going over high curbs, etc. When I installed my underpan, I slipped it between that black plastic piece and the car's body to hold it in place before drilling and tapping screw holes through to the metal body.

[AndrewJ]

So, first off, cut the middle out of the ultra-classy plastic wheel covers.
It cuts pretty easily with a utility knife, but for the thicker bits a Dremel works better. (and it's harder to slice off a finger with a Dremel )




Now trim it up so that any protrusions on the top side are minimized.





And then attach your pizza pan to the what's left of your wheel cover. I used some liquid nails-type construction adhesive. It looks like it'll hold up well, but just in case it doesn't I have some stainless steel wire I can thread it together with.





And here they are installed.
If you look closely in my photo from yesterday you can see that I greased up the wheel where these hubcaps press-fit in. When I tried it yesterday they really took some effort to go on, and they didn't come off well. Now they're much easier (but not so easy that they'll come off all on their own)





I'm going to give these a week or so of driving before I do the rear wheels, just in case there are any changes I want to make.
The neighborhood cat approves.

[SVOboy]

Looks great! What's next?