aero idea for our cars

**MBH** · 10-09-2008, 09:57 PM

I know I know, this sounds ridiculous, but I think it could do some good for our cars.

Anybody know if there would be much if any benefit for making a smoother underside on our cars? Our cars aren't exactly the most aerodynamic things on the road, so I was wondering if there was something simple we could do to our cars to get a little bit cleaner aero. I was thinking of fabbing something like the picture below, but wanted to hear some opinions first. I know that it probably wouldn't do much until after 80mph or so (if at all), but sometimes that darn gas pedal gets stuck

underside of a subie wrx with an aftermarket under tray

Rough photoshop of what I'm talking about on a Brian's SN95

without:

any good pictures of a mustang underbody would be appreciated :)

I'm aware that this would make oil changes a little more time consuming, but that doesn't bother me.

What are some potential concerns you guys could think of? The only things that come to my mind are - it coming off while driving as well as the changed airflow inhibiting some things to cool like they did before.

**97LaserRed** · 10-09-2008, 10:29 PM

DAMN ur sneaky hahaha when u take that pic!

if they made somthing cheap id prob do it just to protect underneath. my cars not fast enough to need anything like that.

here you go Bo.........
http://www.youtube.com/watch?v=8lYBVi3ALWA

**MBH** · 10-10-2008, 11:03 AM

Wow, thanks for all of the feedback guys! You guys are better than the big forums

Bear with me on the ghettoness of this idea, because I'm just thinking about it in terms of the resources I have available to me... I was thinking of taking a sheet of cardboard and then marking and trimming everything off to where I would want it to be (ex: mounting points, edges, etc.) and noting how everything bends and angles then going to town on a piece of sheet metal to replicate it. I don't think it would be all that tough to do like that.

I'll definitely lurk over on corner carvers when I get a chance, thanks for the link Dan!

Also, as far as heat goes.. that is one of my two concerns for this. I'm not sure if that would prevent some airflow over the engine that would be unfavorable/harmful - and I don't have the means to datalog that type of stuff :(

Rob, I've had the idea of making a fully flush underbody like that one you posted on the s2k ever since I've been under my car and pictured how poor the airflow under it must be. I thought about welding it it to my FLSFC's lol

Originally Posted by 97LaserRed

here you go Bo.........
http://www.youtube.com/watch?v=8lYBVi3ALWA

bahahahaha, don't lie - if I was Asian I'd be a ninja

**biminiLX** · 10-10-2008, 01:05 AM

Bo, yes it definitely would help. I read an article in Hot Rod about a car they were taking to the salts and it highlighted a lot of little tricks that are beneficial. Front air pan and rear diffuser (see that new Saleen SMS prototype anniversary car) would be easy to adapt to your car. Plus, its a Mustang so somebody somewhere has to make aero stuff :)
Might talk to the local guy with that land speed Cobra, I'm sure he's done a few things. Plus, Mike knows him.
-J

**95riosnake** · 10-10-2008, 07:35 AM

As for the oil change concerns, a small detachable access panel area could be built into the belly pan using dzus fasteners.

**sweeney1030** · 10-10-2008, 09:14 AM

one problem , it will hold heat in the engine compartment and we all know how much fords love extra heat.

**coralcoupe1993** · 10-10-2008, 09:48 AM

Originally Posted by sweeney1030

one problem , it will hold heat in the engine compartment and we all know how much fords love extra heat.

I dont know but I know it helps some of the Vette guys.

**coralcoupe1993** · 10-10-2008, 09:48 AM

I really like this!

**mineralrob** · 10-10-2008, 10:15 AM

I know for the s2000 they make a full carbonfiber underside. Would be a cool idea.

**mineralrob** · 10-10-2008, 10:21 AM

here goes a pic

**RUTHLESS** · 10-10-2008, 10:37 AM

This reminds me of how hard it was to get to the oil filter on my Subaru STI. It had all these plastic plates on the bottom of the car and this small hole with a rubber flap that I guess should have been big enough for a small child to use to change the filter. Oh and dont even try to get a filter wrench in there. This was one of the reasons I went to the K&N filter with the nut welded to the end.

**Killercanary** · 10-10-2008, 11:57 AM

I like this idea too, I did a quick search and found this:

https://www.secureway1.com/alston/in...?productID=228

My concern besides heat would be an increase in lift at high speeds.

**MBH** · 10-10-2008, 12:02 PM

^interesting! I wonder what the product actually looks like?

**sweeney1030** · 10-10-2008, 12:07 PM

can you imagine hydoplaning at speed with one on a lowered mustang, that would be hairy. Vettes cover the rears more thean the fronts for that reason.

**MBH** · 10-10-2008, 12:08 PM

Originally Posted by sweeney1030

can you imagine hydoplaning at speed with one on a lowered mustang, that would be hairy. Vettes cover the rears more thean the fronts for that reason.

Since it was built, my car has been in the rain 3 times. I'm not worried

**somethingclever** · 10-10-2008, 12:08 PM

Race Bronco did this on SVTP....atleast in the rear..not sure about the front. He had good results.

it's not really new...ever see the underneath of a vette..or any newer foreign exotic?

**MBH** · 10-10-2008, 12:09 PM

Originally Posted by somethingclever

it's not really new...ever see the underneath of a vette..or any newer foreign exotic?

I thought I put it in the first post, but I didn't. The reason I posted the subie picture is because it is aftermarket - but I'm well aware of the flat bellypans of the CGT, FGT, Z06, GTR, etc.

Thanks for the name, I couldn't think of who it was I just knew it was an orange coupe

**MBH** · 10-10-2008, 12:20 PM

OK, now don't laugh because of the nature of the sources, but check this out

on a saturn (not me, nor my car)

more: http://s75.photobucket.com/albums/i3...emysan/saturn/

I'm going to do a lot of reading in this later this weekend I think:
http://www.gassavers.org/forumdisplay.php?f=11
http://ecomodder.com/forum/aerodynamics.html

cause I wanna save gas and the environment, ya know? LOL I should post up "what should I do to my hummer to make it more eco friendly" on one of those forums and see how long it takes to get banned.

**03 OW SVT** · 10-10-2008, 02:23 PM

My wifes Subie Legacy Gt had one of those except it was plastic. It looked pretty cool except as you said it was a PITA to change the oil. Also the couple of times I worked on it (the car) and dropped a nut or bolt it never fell the whole way through and I had to take the bottom cover off to fetch what i dropped.

We also had to have it repaced once because we ran over a dead critter and it ripped half of it off.

**Martin0660** · 10-10-2008, 02:37 PM

I've got far bigger "aero" issues with my Capri than cleaning up the bottom side ;) Sort of like a cinder block in the wind, but it still has some style :D

none the less, you might be much further ahead with a splitter / air damn to keep the air out of there than smoothing the flow when it gets there. Also you can manage the air through the front much better.

Bob Myers