AlexO35

iTrader: (7)

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 ****, 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

miataspeed1point6

iTrader: (1)

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









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.

Zabac

iTrader: (39)

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

Braineack

iTrader: (62)

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










i believe this is what he wants to see..

Joe Perez

iTrader: (8)

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

hustler

iTrader: (6)

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

y8s

iTrader: (8)

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 **** 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.

AlexO35

iTrader: (7)

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

Splitime

iTrader: (24)

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:
More of that rear bumper style here.



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:

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

quadmasta

iTrader: (1)

LMAONADE


Are those Wrangler hood toggles?

Zabac

iTrader: (39)

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.

BenR

iTrader: (2)

Do you have any test data?

BenR

iTrader: (2)

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.

miataspeed1point6

iTrader: (1)

Oops.

The_Pipefather

iTrader: (5)

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

BenR

iTrader: (2)

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

Splitime

iTrader: (24)

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.

AlexO35

iTrader: (7)

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

airbrush1

I think it's an re-amemiya car

Dhaark

iTrader: (3)

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