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Old 10-09-2012, 10:54 PM
  #221  
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You need to take this beast to the 2013 Ultimate Track Car Challenge!

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Old 10-09-2012, 11:31 PM
  #222  
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Originally Posted by motormechanic
did you build the mounts yourself or where did you get them?
The centre mounts that go to the subframe are from Henry at KazeSpec Engineering. These are the prototypes as u can see i had to space them up to ensure it was flat. The mounts that he will be selling have already been modified so no spacing required. He also offers front mounts and side mounts together as a whole package.

heres a few pics as i was building it



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Old 10-10-2012, 11:06 PM
  #223  
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Anyone ever used a spoiler on a track Miata? My car is a dual purpose CSP AX and HDPE car, wouldn't mind doing the CSP allowed aero but there isn't much info on spoilers out there.
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Old 10-11-2012, 01:18 AM
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No no one has ever used a spoiler on a track miata.
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Old 10-11-2012, 08:23 AM
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Originally Posted by FatKao
Anyone ever used a spoiler on a track Miata? My car is a dual purpose CSP AX and HDPE car, wouldn't mind doing the CSP allowed aero but there isn't much info on spoilers out there.
I feel like the drag would kill you. The sister car did a back to back run test of full CSP aero and aero removed with no front bumper (because the splitter is permanently attache to it). With aero removed there was noticeably less drag even at atuo-x speeds, but the car was significantly less stable at speed. CSP aero makes sense for CSP, it doesnt for anything else.
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Old 10-11-2012, 08:59 AM
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Originally Posted by ZX-Tex
What is the point of all this information? DIY Aero FTW!
Great pictures and general write-up.
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Old 10-11-2012, 08:59 AM
  #227  
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We can use mine as a template if you want! I have extra of the same material also you would just need mounts and stuff which is not big deal.

Originally Posted by FatKao
Anyone ever used a spoiler on a track Miata? My car is a dual purpose CSP AX and HDPE car, wouldn't mind doing the CSP allowed aero but there isn't much info on spoilers out there.
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Old 10-11-2012, 09:01 AM
  #228  
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Originally Posted by triple88a
No no one has ever used a spoiler on a track miata.
Just made me lol at work. well done.
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Old 10-11-2012, 12:35 PM
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Originally Posted by triple88a
No no one has ever used a spoiler on a track miata.

I could be missing the sarcasm here, but I know Emilio has used one in the past. Also the member "the pass" has/had used one in the recent past. I don't think they were at the angle of a CSP auto-x car, but they were on the car.
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Old 10-11-2012, 01:36 PM
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Originally Posted by Midtenn
I could be missing the sarcasm here, but I know Emilio has used one in the past. Also the member "the pass" has/had used one in the recent past. I don't think they were at the angle of a CSP auto-x car, but they were on the car.
I think he was trying to be sarcastic and was assuming wing = spoiler.
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Old 10-11-2012, 02:11 PM
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A spoiler would work on the track, but the DP/CSP spoiler like on my car would be way too big for track speeds. Here's my AutoX DP car with latest areo mods:







PS. For the track I kept my stock deck, and will someday get a wing.
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Old 10-11-2012, 07:21 PM
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Originally Posted by Ski_Lover




Dam that looks tough.

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Old 10-12-2012, 12:03 AM
  #233  
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Originally Posted by FatKao
Anyone ever used a spoiler on a track Miata? My car is a dual purpose CSP AX and HDPE car, wouldn't mind doing the CSP allowed aero but there isn't much info on spoilers out there.
I've been meaning to build one all year but never got time for it. A long, low angle splitter has potential to be awesome on a track miata. You could definitely rig up a mounting system to use the same spoiler at a really steep angle for autox and then lay it down for the track. Give this book a try if you want to get a good idea where to start... I found it to be a very good starting point for learning aero stuff.

Competition Car Aerodynamics: A Practical Handbook,2nd Edition: Simon McBeath: 9780857330079: Amazon.com: Books Competition Car Aerodynamics: A Practical Handbook,2nd Edition: Simon McBeath: 9780857330079: Amazon.com: Books
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Old 10-12-2012, 02:35 AM
  #234  
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Originally Posted by FatKao
Anyone ever used a spoiler on a track Miata? My car is a dual purpose CSP AX and HDPE car, wouldn't mind doing the CSP allowed aero but there isn't much info on spoilers out there.
If you mean a real spoiler and don't actually mean wing, you can see my spoiler in my sig. Currently it is ~10" long in the center and sits at ~40* angle. I am going to either trim it down to 8" or decrease the angle to ~30*, but I am undecided between which route to go.

But anyways, yes - it's been done A wing is far better, we all know that - more downforce with a much lower drag cost, but I had alumalite sitting around, not a $700 wing, hence the spoiler. It does work. What I would like to do in the future when I do get a real wing is to do a spoiler like mine but smaller with less angle in conjunction with the wing.

If you have anywhere near stock-ish power levels, I would recommend doing a spoiler with a very adjustable angle - you're going to want it fairly steep for autocross, but you're going to want to drop that sucker down to near horizontal for the track. Close to horizontal, it doesn't function to create any "downforce" but it does offer improved tail aero by effectively extending the length of the tail of the car. The boys at 949 have used spoilers in this way with good results - mostly to improve fuel consumption in Endurance Racing - but that says a lot. If it helps the car use less fuel, then that means it is reducing the drag on the car. This would be the optimal way to use a spoiler for a low-hp miata. At any significant angle, the drag is going to hurt your straight-line speeds enough to negate any benefits of more grip in the corners.

Edit: and to throw in one more bit of info related to spoilers, it's important to understand why/how they function, because they don't do what most people assume they do. (And I have derived this just from gleaning info from as many sources as I can so please, if I am incorrect about any of this, someone chime in and let me know) Many assume that the spoiler is there to "catch" the air coming down over the rear of the car and that the force of the air hitting the angled spoiler pushes down on the spoiler, which is mounted to the trunk, and therefore "downforce" is created. This isn't very accurate. The better way to look at it is that the entire car is an airfoil of sorts, because with all things aero, the whole picture must be looked at to see how one piece of the puzzle benefits the package. For the same reason that race cars apply slick under-trays to speed up the air travelling under the car - since fast-moving air under the car and slower moving air over the car creates a pressure differential and pulls the car downwards, a spoiler helps to stall that air moving over the car - slowing down the air going over the car helps to increase that differential between top and bottom of the car - so it adds to the whole package of attempting to create fast air under the car and slower air on top. Obviously though, slowing the air on top costs drag, while speeding the air under the car eliminates drag, so in terms of what is a "better" thing to focus on, under-car aero is going to produce the best improvements with less downsides than over-car aero.

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Last edited by ThePass; 10-12-2012 at 02:53 AM.
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Old 10-12-2012, 03:26 PM
  #235  
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Yep, talking about a true spoiler.

Sorry, lost track of this thread for a few days. What I was hoping to do would me make two spoilers that use the same attachments or some trick attachments that I could swap out to change the AOA(?) between track and AX fairly easily. I agree on all points about undercar aero and wings over spoilers, but those are the prices I pay to keep the same letters on the side of my car. The main goals here would be drag reduction rather than down force. One other limit is that I can't go past the bumper when viewed from above so I may be somewhat limited in how much benefit I can get from extending the bodywork.


For those that have run large front splitters do you think I'd have any chance of getting a balanced car with a CSP splitter and a low drag spoiler?

Here is what comprises a CSP legal splitter, it's a bit less functional that I'd imagine most here have built.

A spoiler/splitter may be added to the front of the car below the
bumper. It may not extend rearward beyond the front most part
of the front wheel well openings, and may not block normal grille
or other openings, or obstruct lights. Splitters may not protrude
beyond the bumper. Openings may not be used for the purpose
of ducting air to the radiator or oil cooler, but they may allow air
to flow through a permitted oil cooler provided no ducting is used.
The spoiler may not function as a wing.
Something tells me I'm going to be buying a spare bumper skin and trying some stuff out when I hit the track next year, worst case being swap an OEM skin on if I can't get it balanced.
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Old 10-12-2012, 03:31 PM
  #236  
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If you make the normal csp style air dam along with the splitter, a normal csp style spoiler in the high downforce config is pretty even. If you make the Davis style csp air dam then you will make more front downforce than a normal csp spoiler makes rear downforce. Davis splitter V1 made WAY too much front downforce, so we had to drill may big bleed holes in the air dam to tune it.

With a low drag spoiler, good luck.
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Old 10-12-2012, 03:43 PM
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Not super helpful, but fun to read:

Brokecore Miata aero build and testing. As far as I know, Jerry never really took the car to any "serious" tracks - mostly just fast autocross/mini roadcourse stuff.
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Old 10-12-2012, 10:39 PM
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FatKao -

I definitely think you can make a splitter that fits within those rules that will have a benefit. In this instance, the fact that OEM miata bumpers curve backwards from the centerline of the car down is good because that gives you something like 2"-3" that you can extend the splitter out from the bottom of the bumper before it goes beyond the furthest out portion of the bumper. Obviously, it's not as optimal as a bigger splitter - nothing built to conform to a set of rules is - but it should definitely help, and in your case since you can't do much for rear aero to balance out a splitter, an "optimal" splitter would be too much.

Your biggest restriction for the back is if you're not allowed to have the spoiler extend further back than the rearmost part of the car. On the up side again though, the trunk lid edge sits a couple inches forwards of the rear bumper edge when viewed from above, so you can still hang it off the trunk a bit and be within the rules. So much for a near-horizontal spoiler of any significant length though.

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Old 10-14-2012, 01:10 AM
  #239  
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I had planed what Ryan talks about, going with a shorter version, more raked, for my Track day OEM deck, but the 949 Supermiata wing sure looks tasty
http://949racing.com/Supermiata-GTC-...a GTC-200 Wing
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Old 10-15-2012, 12:40 PM
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What are your thoughts between these two splitters/airdams












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