Looking for pics of real aero parts
 

So I've built a pretty hefty air dam and cut out my back bumper in the name of aero. Pulled an average gain of 3 mpg so it is effective, but its not done.

I'm looking for pics of NA's with effective aero mods. None of the "Oh I have a race car" ricer shit, but real effective parts. Particularly air dams (mine's not quite done) and rear diffusers. Not looking for downforce yet, just a reduction in drag.
--Alex

I can't speak to the effectiveness of these, but I saved them because they looked like good parts to copy myself.

Attachment 212423

Attachment 212424

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I have seen diffusers on CR, but I have no idea if they work. I doubt I will ever make one, so I haven't searched very hard for real miata race cars with them.

For the rear, just do what stealth did...it seems to work well.

all those posted are for increased down force, not the removal of drag.


things like front chin spoilers, undertrays, skirts, difusers, etc etc, would be to help reduce drag...thus is increase in MPG not decrease ;)


http://i295.photobucket.com/albums/m...tures/P1-2.jpg

http://i295.photobucket.com/albums/m...s/IMG_0090.jpg

http://img206.imageshack.us/img206/1...00largegb6.jpg

http://img237.imageshack.us/img237/4...07largejd2.jpg

i believe this is what he wants to see..

In this first pic, you can't really see much because there's a blue Miata in the way.

that blue car is very good for round-eye. I need that bumper.

actually the lips (horizontal -- ) and air dams (vertical | ) do a very similar job. they keep air from going down under the nose of the car. that helps both keep air out from under the car where shit is fugly aerodynamically and also creates a low pressure region under the car that helps improve pressure differential across fun parts like the radiator.

air holes in the rear bumper are for a similar reason.

diffusers are more for downforce. they "spread out" so that the air also spreads out (rarifies), speeds up, and creates a low pressure region. if you have low pressure under something and high pressure (or atmospheric) above it, guess what you get? downforce.

so if you imagine a giant wing... flip it ,,umop apisdn,, and put four wheels on it... you have a race car. smooth underside that rises at the back.

Sweet. Thanks for the pics. Any more of the white car a little closer?

My air dam is a Track Dog knock off really, but I haven't decided how to finish the ends and incorporate the splitter. I like the idea of doing the nose and front undertray in one piece. I am a bit concerned with blocking off the bottom of the engine compartment without a way to vent heat properly. I'll probably have to go with a vented hood.

While I agree that usually the purpose of diffuses is fo downforce, they also do a nice job of releasing the underside air back to ambient thereby reducing drag. That and I don't like the drilled bumpers. A bit too much rice / drift for me. Basically on mine I took a template for a FM dual exhaust, cut out the secong hole and connected them. Its really quite subtle due to the height of the car. Now I just need to transition that cutout into the underbody of the car. So while it may not be a true diffuser, it should help put the air back nicely.
--Alex

I'll link you to my random miata picture gallery. Lots of random aero/motor etc.. stuff.
http://s295.photobucket.com/albums/m...ta%20Pictures/

The white car is actually light blue i think, here is a closer shot of that fender mod
ie: http://i295.photobucket.com/albums/m...ictures/p1.jpg
More of that rear bumper style here.
http://i295.photobucket.com/albums/m...rdiffuser2.jpg
http://i295.photobucket.com/albums/m...ersplitter.jpg

I think we are mixing up "difusers" here also. The red car up above with the "drilled bumper" is mine. The piece used is mainly designed for drag cars to trim what is normally either a missing bumper or a severly hacked one. It's main purpose is to allow air to flow through instead of getting caught.

It's aero effect is quite different from an underbody/aero difuser. Which will flow the air more effectively and block that entire area off. Thus allowing the air to be shaped in a way that speeds flow (as mentioned above) and creates downforce.
ie: http://i295.photobucket.com/albums/m...s/IMG_1186.jpg

My use is neither ricey or ******* btw... its a track car :p (I'm fairly sure you weren't 'picking' on it... but anyways)

LMAONADE
http://misers.org/pictures/Something...l/lmaonade.gif

Are those Wrangler hood toggles?

That blue car would look nice if it didn't have that super gay sticker and round hook type of thingy just hanging there randomly.

Do you have any test data?

It's a tow hook, that car looks to have a full cage so it probably competes wheel to wheel. Tow hooks are required for wheel to wheel racing, sure it could be placed in a more pleasing manner, but it looks 100% as functional as the rollcage.

Oops.

You're right, looks like there is a Ford RS200 in the background.

That is NOT a RS200. It looks more like one of those jdm body kit miatas, probably pitcrew.

Not going to do the homework for you. You'll see how the underbody panels differ in use vs simple bumper opening aero.

And that ugly thing is most definitly some nasty jdm bodykitted miata.

There is some pretty good reading in "Racecar Engineering". I don't have the links to the articles anymore though. It gives a pretty good run down of diffusers. The aero holes are just common sense. They've been doing that on race cars for years. Take a look at the back bumper sometime. Sits there like a big old parachute air brake.

Splitime: Thanks for the link. Whole crap load of pics to go through. You're right, wasn't picking on your car with the ricey bumper hole crack. I've just been tainted by Hondas doing it for the "look". Well, one particular Honda that I can't stand actually. For a track car though, I get it.

What is the purpose of the fender mod on the white car?
--Alex

I think it's an re-amemiya car

Where can I get a working wing like the one on the blue car in the post by miataspeed1point6?

Best bang for the buck (as in actually works but you get to keep both kidneys)
APR Performance it's where I got mine.

For the fender mod, think of it like M3 fenders... ricey on the honda varients too ;)

But they serve to vent the air from that area when you are fender liner less.

i just want the big mouth on that blue car for mine. That would ease all my stress.

The fender mod directs the air that the wheels blow around around the car instead of into a flat wall.

The fender vents in a Z3 and the portholes in older Buicks are for heat extraction.

I do my own homework. An answer like that shows you probably haven't really done yours.

http://i2.photobucket.com/albums/y11...tGotServed.jpg

I figured it's a tow hook, but my god, that thing looks fucking retarded and probably scrapes everywhere, even on takeoff on a flat surface. It just looks stupid and out of place. I am all for tow hooks if needed, believe, I used mine a time or two, lol, but that shit is just JDMfugly!!!

Which model do you have, and how tall is it? Did you have to fab something up to make it taller than what they offer?

AS-105502 GT-II (Aluminum)

Mine is 16" tall the GT-I is 13" and the GT is 10" I didn't do anything to make it taller. I have to stay withing the SCCA SM2 rule set which limits the wing height to 6" above the windshield header. Ideally a little bit higher might be better. There are a couple of models depending on what you are wanting to do with the car.

Some autocrossers are replacing the upper element which is 5.5" with a 7.5" one. It is still within the rules, but I personally think the 5.5" is enough.

To each his own, that's what makes it fun.

You are going to have to do alot more than that to bait me into a lame e-fight.

Go look at aero models of underbody diffuser systems vs just opening up the bumper and using normal bodywork as the "aero". They do similar yet different things. For the money/ease... I'm content with opening up my bumper.

It doesn't have to be a lame e-fight. I just asked if you had any data. You could have just said "no, but it looks cool", or "yea it was good for about 2 tenths at the drag strip".

come on, we're diy miata builders. we dont "take data". we go research shit online and generate our own theories based on what we saw and read. there is no data unless someone else* has done the work. and someone else* is often race teams that don't share data.

occasionally someone with toss a magnehelic gauge somewhere (eg hood vents) and get some data, but I think there's like two guys who own miatas that have ever done that.

* "someone else" is my favorite helper.

i have one in my trunk.....still have yet to use it. needs more cutting of my hood and attaching of my splitter.

You don't even need a magnehelic guage, a stop watch works.



Actual testing and modification based on the results is what seperates real aero from the bullshit JDM clubroadster aero.

I think for Dave's build, it wouldn't tell you much. have you heard the saying "change one thing at a time"? :)

Pffftt. Where is the fun in that. I like to build entire cars in one swoop ;p

fine fine. in that case, for one lap / session, cover up the holes?

Heh, I'd need to cover them and figure a way to add the bottom back into the bumper.

I'll provide one simple data point. On a few drag cars I know of... hole chopping of the bumper was worth a couple MPH trap improvement. I'll take it.

3 mpg out of an air dam and a bumper cut speaks enough for me. No other changes. They basically perform the same funtion as the holes. The air dam tries to keep air from getting back there in the first place. The wide cut out lets it out easier.

(Yea, the air dam keeps air out of the "dirty" underside as well and I never did test them seperatly)

--Alex

http://honda-tech.com/zerothread?id=2285480
Attachment 212335

I heard of a guy over here using an F3000 car's rear diffuser, needed only minor fab work to make it fit

Guys.. Anymore info on how to do this?

+1

i know some of you were looking for better pics of the light purple car in the first pic. Well, i came across some...

http://farm3.static.flickr.com/2352/...4680317ebe.jpg

http://farm3.static.flickr.com/2340/...50942a7be1.jpg

+2

That looks silly good