Questions about a body kit.

[Baltothewolf]

Got some ideas for what I want done with my car in the next year, as I plan on running this thing for 600k+ miles. Would a 1-2" lower and a body kit (Blitz if I can find it) negatively affect mpg? I'm not going to put any 'ricer' mods on my car (like a ridiculous tailpipe or turbo) I'm just going for an aesthetically pleasing look to ME.

Oh I was also thinking a low-pro wing as well (one that just sits flush with the trunk and goes up a little). Not one exactly like this, it's just a example:

[nemo]

If you are just going for looks don't worry about it. Most of the body kit I've look at don't show any test information. What you can do is use the tools and information we have like a flat spoiler extended out to the template will usually help. How does the one you are looking at fit under the template? How close to the ground is the front splitter or air dam. Does it have large opening or will it smoothly move air around to the sides.

Posting some front and side view picture may help with the discussion.

[mcrews]

Take a look at the under belly post in my sig. I have an IMPUL kit in my 02 Infiniti Q45 Sport. It 'lowers' the body profile 2" while leaving the suspension stock. Worse decision I made was lowering the suspension 3/4 inch. If you REALLY want to be able to drive it forever leave the suspension stock height.
Stock EPA was 22mpg hwy. after the kit I regularly got 27mpg before any other mods. I had adjusted my driving though.

[Baltothewolf]

So forget the ride height lower and just get the body kit? I haven't decided on a body kit 100% yet, so i'm still looking around.

Oh and just to clear up any confusion, that pic of the mustang was just to show the type of wing I want, not the body kit or paint.

[vskid3]

Do a body kit like this. Aerocivic - Honda Civic modifications for maximum gas mileage - aerocivic.com
Anything else will take much longer to pay off (if ever) unless you get it for a steal. Most of them are made to look "cool", not for function.

Can you really get 600k miles out of that car? Rust will likely take it before then unless you're driving 50k miles a year. Factor in the auto tranny and you'll likely end up spending more by keeping it that long vs buying a new beater every few years.

[aerohead]

Since so many of the members have notchback cars I dug deeper into Hucho's book and SAE papers.Here are some of the things we have to consider which affect the back of the car:
*roof curvature (camber)
*roof transition to backlight header
*angle of backlight
*transverse curvature of backlight
*C-Pillar contour
*trunklid (boot) height
*trunklid (boot) length
*percentage of this area compared to the overall length of the car
*quarter panel boat-tailing
*underbody of the car
*presence of a diffuser or not
*presence of wheel skirts
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This sort of 'knowledge' has been around since 1976,so there's a good chance that Toyota has already 'optimized' the Camry in the Japanese Auto Research Institute (JARI) wind tunnel.Toyota may have their own tunnel.
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A comparison to the 'Template' might tell something.Many 2013/14 cars have the 'Template' running right through the center of their spoilers.This wouldn't be arbitrary.

[kach22i]

VIDEO
Video: 2012 Ford Mustang Boss 302S Wind Tunnel Testing | StangTV
<iframe width="560" height="315" src="//www.youtube.com/embed/Gr40fdYmd2I" frameborder="0" allowfullscreen></iframe>

Stills:
Video: 2012 Ford Mustang Boss 302S Wind Tunnel Testing | StangTV




FR500S in Wind Tunnel - The Mustang Source - Ford Mustang Forums


Based on the images and video I think a rear deck spoiler like the one below would allow for a clear separation of air better than the one proposed which is more inclined for down-force.

2010 Steeda Q350: Beyond Expectation – Beyond Compare « Steeda Blog


Then again, perhaps nothing at all would also work because it appears air flow detachment occurs at the lower 1/3 of the rear window.

Below is an example of air leaving the car rear deck lid (non-Mustang) cleanly.
http://www.advicesisters.com/lifesty...gofurther-ford

[aerohead]

These notchback and aeroback cars are the toughest to figure.
Even if the spoiler corrects the flow on top,it does nothing for the sides,which are still part of the separation line.And it is the aggregate pressure at the separation line which determines the base pressure of the wake and subsequent pressure drag.Which is what we're going after.
An improper spoiler could affect the vortex-induced downwash which helps keep the flow attached as much as it is,as the flow see's the longer 'step' in front of it.An up-kick to the spoiler complicates matters even more.
With a wind tunnel we could just read the force measurements and know immediately if our mod was heading in the right direction.Smoke is good too!

[kach22i]

Originally Posted by aerohead

.........An up-kick to the spoiler complicates matters even more.

Great information, really puts things in perspective.

I'm convinced all of these types of aftermarket spoilers are focused on down-force (and sales) and not fuel economy.

The one tested solution to these styles of roof is still very attractive to me.

Merkur wing
http://ford-sierra.lt/new/e107_plugi...c.php?31322.13


However, I'm not versed on if the main goal was air flow attachment, fuel economy or down-force.

[Baltothewolf]

Originally Posted by vskid3

Do a body kit like this. Aerocivic - Honda Civic modifications for maximum gas mileage - aerocivic.com
Anything else will take much longer to pay off (if ever) unless you get it for a steal. Most of them are made to look "cool", not for function.

Can you really get 600k miles out of that car? Rust will likely take it before then unless you're driving 50k miles a year. Factor in the auto tranny and you'll likely end up spending more by keeping it that long vs buying a new beater every few years.

I do drive around 50k a year, and I'm not looking to add it specifically for mpg, I'm just making sure this isn't going to lower my MPG, even if it doesn't increase my MPG I still want it. This mod is for looks, nothing more.

To be honest, I got pillar gauges specifically for the look factor. I spend so much time in my darn car I want it to look 'cool' to me and still get good gas mileage.

Seeing the posts above, if a wing no matter what style I get will lower mpg I'll just leave it out.

Oh also about rust, I live in the desert, it hardly ever rains here.