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.

https://www.miataturbo.net/attachmen...ine=1461603486

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.

https://www.miataturbo.net/attachmen...ine=1462127617

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.

https://www.miataturbo.net/attachmen...ine=1462127617

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

https://www.miataturbo.net/attachmen...ine=1462164559
https://www.miataturbo.net/attachmen...ine=1462164559

Awesome!

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

#2 is lowered

Oh wow, I knew it was a stupid question :facepalm:

Thanks mate. I'll look into a spoiler then.
Time to google away to fab one up.
Got any quick hints on angles for a track where max I'd see is maybe 180kph?

Click the link, and all will be revealed!

Ed, PM me, I run those circuits, both with and without aero.

No air dam,stock na bumper with gv lip and splitter. I just don't want to put the splitter on and have the rear end want to come meet the front haha.

Pmd Gee Emm

I didn't realize that, my bad :facepalm:

Just when referencing that for design dont forget that 6 has a larger surface area on the splitter than 4 due to how to test was setup so its not conclusive on which style airdam is better.

I would disagree - not about the difference in splitter surface area but in the (lack of) conclusion about which config is best. 6 is clearly better than 4 in terms of drag. Even if you tweaked 4 to match 6's downforce, 6 still wins the L/D contest by a big margin.

Yeah more down force with less drag has me like :cjerk:

I have used both 4 and 6 without changing anything else to the car and 6 has allowed for a higher top speed but about 3-6 km/h.

Was there any noticeable difference through turns at high speeds?

Not that I could feel.

Huh, interesting. How hard were you pushing it?

Hey guys, so just some relevant facts on my car and then ill get into my dillema

330whp 310wtq 3.63 rear EFR6258 20psi
XIDA 700/400 Gen 2
15x10UL w/ 245 Maxis RC-1
2550lbs with Hardtop installed

I was looking at the BBFW lexan spoiler, but a friend gets deals with some distributor and can get me a GTC200 with risers and a gurney flap, for $865 shipped which isn't bad at all. I know I'll have to build some kind of front aero to balance either setup, but just looking to get some insight on what people have tried before. I know the BBFW will be functional, but probably not AS functional as a proper wing on uprights.

What would miataturbo do? Do I go for the Lexan spoiler or for the GTC wing? Do I use the risers or not? I've heard of some issues with the stands being designed for an NA trunk and not really working on an NB too well. Should we get just the wing and try to make custom mounts for it? Chassis mounts? So many dilemmas here

I do have a spare trunk lid for either setup since I only do maybe 5 track days a year and the rest of the time is just spent on the street and cruising around. Probably would not permanently run either wing unless I loved the look

For front bumper, I was thinking of just building a giant plastic dam, basically similar to the Super Miata setups that most have. I can pick up a spare Ti bumper for the MSM with a smashed bottom, cut it along the fender line, and then use rivets or something to attach a giant front dam similar to 949racing's Crusher IIRC. Then, use alumalite to build a diffuser that will mount to the subframe and sit flush with the bottom of the front bumper, and stick out a few inches. Not sure on details with this, but something like #6 from that pic ThePASS posted. I am leaning towards the BBFW just because of cost and other expenses I have with school but basically wondering if the GTC200 is really worth 3x as much money.

850 shipped doesn't seem like a special deal tbh. The gtc-200 isn't a fantastic wing in terms of L/D. It will be effective if you keep it high but at a significant drag cost. The bfw spoiler is functional and the price is right. For me I would go with a bfw spoiler and/or save money for a GT-250. I wouldn't bother with anything in between those.

Supermiata air dam is effective/cheap/worth it. A splitter with the air dam is better to balance a wing. You're still going to want a plywood undertray behind the SPM air dam to get the most out of it.

To be fair the same package shipped from 949 was 1080 or so.

I understand why a splitter behind the bumper is needed, airflow and it reinforces the bottom of the bumper. However, what's the advantage of plywood over alumalite in that department?

imho, if you are spending money on a functional wing, get the best...

Singular Motorsports Aero Wing for Miata

Trust me, I drool over that and that's going to be THE wing I get down the road. Right now, even considering the high cost of the blackbird spoiler, and the spare bumper I'm getting, I don't expect to spend more than $500 on both aero pieces. I'm not a very experienced track driver at this point so I figure starting small with simple aero mods is a good way to get an understanding of it.

I did order the blackbird spoiler and am going to start figuring out the front bumper next week. My friend already has alumalite we can use for the splitter so I'm just waiting to hear why/if plywood is significantly better, otherwise I'll roll with what we have for now. Found the HPDE stuff for around $30 for a large piece to do the bumper. Sound right?

ah, ok, that makes sense, both front and rear for 500 is great.

Someone asked me to post a pic of the splitter on Creampuff from the bottom, so here it is -
https://www.miataturbo.net/attachmen...ine=1464118436

Question for running flat underbody.
Would it not be possible to create a vent in thepanel to let heat out? Similar idea to bonnet vent using high and low pressure. Would the body side of the panel have low enough pressure to be sucked out by air flowing underneath the panel?

the airflow underneath the panel is what has low pressure, and would suck the heat out. You have it backwards.

Yes, yes I do. Re read it.
But would that work well enough to reduce heat around gbox etc without disrupting anything else?

It would help. However, venting air to the underside of the car isn't my top choice. You wouldn't put vents in the lower half of a wing's endplate because you want low pressure under the wing, don't want to move pressure from the high side to there. But, if you've got to do it for heat management, don't want to use dedicated coolers, and can't move enough air down the tunnel and out the back to keep operating temps of the trans and diff in the green, then vent away.

Thanks for the answer.
I had been wondering if it would be useful or not.
That clears it up.

Edit: Uh, wrong thread.

Here is a link to a home-built, all carbon fiber (other than the pillar with vin) Sierra Cosworth 500 that was at the Dragon last weekend. Flat floor from splitter to diffuser. Gene, the gentlemen who built it, a retired network engineer, started with a Merkur, ordered a body kit from the UK, modified it to suit his tastes, and then made molds from it. The car was very well put together and had a race weight of 2000 lbs. Also in there is Andrews SPU Miata that had a fantastic time for its first outing at the Dragon. He's regularly an autocrosser and did a hell of a job.

https://www.flickr.com/photos/141028...7669618661646/

Thats a pretty wicked looking Cosworth. I have never seen a alternator ran off the driveshaft before. Google tells me they make kits to do it, never would have guessed.

It's fairly common with the roundy round guys, with the downside being that unless you're up to speed, it's not charging.

The shit that's hiding in Kentucky...

That's amazing. There's another dude in that area of KY that built a really badass full carbon SN95 mustang track car a while back. Wonder if it's the same guy.

I got the impression this was the only one, but not sure. He works with a local high school every year on some sort of eco-modder type competition, helps them with all the composite/design work, and I guess they've won about 10 years in a row now. His wife was racing too, a fairly simply prepared SN95 Mustang, but she was no joke for a first timer at the hill.

Have I just been living under a rock? Is there a closed-course competition held at the tail of the dragon?

Chasing the Dragon hillclimb is a CCR-SCCA event held once or twice a year. It's on Santeelah Road in the Joyce Kilmer National Forest, and is not part of the Dragon itself, but runs right next to it. It is a wicked road though, with decreasing radius turns, esses, long straights, and the area is just gorgeous. Check out dragonhillclimb.com and ccrscca.com. There is also a Facebook group for it. If you do a Google Maps search for "Chasing the Dragon Hillclimb Start Line", it will pull up. It won SCCA event of the year previously, and is unlike anything you will ever drive at speed.

New wing for Morpheus (the new Blackbird Fabworx race car), it's an APR Performance GT-1000 swan neck mount, and we're building a DTM style DRS into the mounts -

https://www.miataturbo.net/attachmen...ine=1466209106

Not the smallest wing I've ever had, I'm 5'8" -
https://www.miataturbo.net/attachmen...ine=1466209106

I'm picturing the mounts for that coming off the back of the hardtop and grabbing it from above like that koenigsegg wing.

I'm looking at the same wing, but not in a swan neck. Did you get it in the full 71" width or was it shortened? Keep us posted on the progress and how it feels on the track. What are you doing upfront to offset the wing. Not bad for a $2000+ wing

Full 71".

They are going to be coming from the inside of the trunk, in a similar fashion to the way they are done on DTM cars.

Funny, I put that website (dragonhillclimb.com) together years ago. Not sure if Ted's still involved with it, but I'll have to make it up there someday.

This is an interesting video showing the comparison between my Miata with a dodgy wing and large rear spoiler vs rear spoiler only.
Take note of the steering wheel angle.
I am going on Sunday with a wing I built myself, and the rear spoiler has been replaced with a large camm tail. Top speed with the wing and spoiler wasn't good.