I just built an air dam from the orange .070 material above and didn't like the way it worked. I never tried it on track. It was very difficult to keep from warping a little bit during installation, and when it was installed it just felt slightly too flexible.

My setup is a little bit different than a SuperMiata though, as I do the Home Depot splitter thing rather than an undertray behind the dam. In my case, the air dam is only attached at the top at the bumper and not to the splitter. I think NB's require less height from an air dam too.

I went back to the .100-.125" thickness material. "Chevron Blue" almost perfectly matches our Mariner Blue too. Both materials are really inexpensive so trial and error isn't a bad thing.

Also, a Spectre 8148 intake adapter fits 3" brake hose perfectly. And they are super cheap at around $5-$6 each.

 

You're right. Just checked mine, it is indeed .100. Edited my previous post.

 

Wow that looks good with a splitter, i'll definitely have to consider doing this mod once my miata is a full on track car.

 

Here is my copy of the SuperMiata front end. it is the .100"+ circle track stuff held on with Dzus fasteners so that it is quickly removable so I can load the car on the trailer. The under tray is 10mm Alumalite and the radiator duct is hand made fiberglass. The stuff all comes off very quickly, and in making it that way, took way too much time to build. it should be back on track shortly, just waiting on some 2-1/2" brake ducts from Andrew at TrackSpeed.

 

I really like the fiberglass ducting for the radiator. Very clean brake duct ports too.

 

Definitely, I'll have to do something like that when I decide to turn mine into a full on track car.

 

Hi all, new here. And signed up because of this aero thread.
Trying to read through everything and make good sense of it.
Have come to the conclusion that since I will not be running arear wing for some time it's a bad idea to build a proper splitter for it. However, can I still make a full flat underbody front to rear without any adverse effects?

Cheers, Ed

 

Added the new brake ducts,

 

I think if you do a flat bottom without properly addressing airflow through the transmission tunnel for the trans and diff, you might end up with thermal management issues, and I could see the tunnel getting insanely hot.

 

How would I tackle that?
Or could I just run a front flat undertray and diffuser at the rear?

 

Eh diffuser works much better with the whole thing flat. You'd just have to monitor trans and diff temps, if they get too hot then add a cooler. Pretty sure multiple people have a full flat bottom though so I'm not sure if you'll run into horrible issues. With the ls3 in mine I'm fairly sure I'll run into heat issues though, but we'll see if how hot it gets in there. When the time comes that will be addressed.

 

Try looking at aero in the classic perspective of "stages" where the first few stages are relatively easy bolt-ons and you then progress into more extreme additions/changes that require more time/money/etc. and which also require more fine-tuning and precision to work well.

Simple, effective aero is hardtop, airdam up front, spoiler out back. There's your stage 1. There's really no reason I can think of NOT to do at least those things. Want to step it up from there? Wing and splitter (with airdam). These things balance each other well and are relatively easy to get right. Just about everyone knows how an airplane's wing works. There's a large pool of experience to draw on with these things so you can easily find the right stuff without wasting much time or money.

As you progress onward the pool of experience shrinks. LOTS is known about complex aero as it pertains to race cars, but first hand experience on the amateur racing level (where 99.9% of forum users fall) is very little, so eventually you're doing most of your own research as you move forward - reading books, technical papers, etc. and/or doing a lot of your own trial/error.

Flat bottom and diffuser are somewhere around stage 4/5/6 depending on complexity. They go hand in hand - a diffuser without a flat bottom is nearly useless - and while they can have big benefits, they need to be done properly to be worth doing at all.

Flat bottoming a car as aero mod #2 just doesn't make sense on several levels.

Side note: a diffuser won't balance front aero in quite the same way as a wing or spoiler because a [proper] diffuser's center of pressure is actually at or slightly ahead of the throat, which should be close to or forwards of the rear axle centerline.

 

Thanks for that reply. All makes good sense. So if I ran a splitter and spoiler for now, what style would suit track work as opposed to motorkhana days.
Mainly Marulan, Wakefield Park and Sydney Motorspory Park (Eastern Creek) if your familiar with them. Not sure where your from obviously.

 

Sounds like you're Down Under. I'm not familiar with the motorkhana term but googling it looks a lot like autocross?

For low speed autocross, you just have to go big and aggressive to get noticeable forces from relatively very low air speed. A BIG spoiler out back with aggressive angle and an airdam with splitter up front do a good job there - the splitter doesn't unbalance the car with the spoiler because at speeds <100 KPH it is just starting to come alive.



For track, look to SuperMiata for the proven spoiler and airdam setup (covered extensively in this long thread) - super easy to implement and it's been done and proven. This aero is like a rock - it just does what it does all day long, with total consistency. Usually the spoiler is set up with angle adjustment so you can kick it down for very high speed track where drag reduction is paramount.

 

Generally speaking,is a rear spoiler (Blackbird spoiler) enough to properly balance a front splitter with no air dam?

 

Do you mean air dam without splitter or actually splitter but no airdaim? If the latter, what's your bumper setup?

 

What about an NA bumper with a GV lip and splitter. No air dam

How much does the air damn+undertray add over an NA bumper.

 

These are questions that have already been answered
(I'm pretty sure this has been posted previously in this thread)

Splitter or Air Dam – Which Design is Best? Hancha CFD

 

Awesome!

 

Wow, this makes me really want that airdam...this might be a stupid question but what's the difference between #1 and #2?