Gotcha and completely understand where you're coming from.

In reality, the street **** or a spoiler is a half-measure. If you're searching for your PBs then you'll want a typical roof-level efficient wing. Also, don't forget about the front of the car! Air-dam is the easy button, but yes I know they're ugly as damnit. The biggest gain to have on NA/NB bumpers is to eliminate that "over-bite" the front bumper has. Getting that taken care of will make the rear aero setup work much better, but also it helps reduce overall lift, yes lift no downforce, on the front of the car.

 

One thing I noticed last year when playing with a GV-style lip is that it made a much larger difference in overall 'settled' feeling of the car when top was down vs up. I know you are asking about the rear, and while I have the 9LR street **** pictured here, I didn't notice a giant difference on the track with it; running with soft top up, NASA HPDE, N/A NA6.

 

@flier129 Any chance you could direct me to a solution for the "over-bite" that isn't an airdam? And why is the over-bite so problematic? Does it encourage the air to cause high pressure underneath the "nose" therefore causing lift?

 

Yes, high pressure builds beneath the nose and lifts it.

 

I have an 02 as well. Front Tupperware kit does wonders for getting rid of front end lift, and I plan on going with something like RTheory front splitter so the front looks mostly "stock". I also have front canards to help with front end lift. For the rear I went with CarbonMiata monster spoiler. I begin to feel it around 90ish MPH. I also have a rear diffuser that's been modified, but it isn't a FULL diffuser as it ends right where my racingbeat muffler is and doesn't attach to the rear diff area like others I have seen.

 

Hello, Have you heard anything back about track car aero? Or did you buy the spoiler? If so, did you notice a difference?

Thank you

 

I've got the trackcaraero wing and it definitely does generate downforce. If I had to guess how much I would say somewhere between insignificant and a little bit.
No data, my butt says so.

Anyway, installed as is I noticed the wing vibrating at speed.
I added rubber stoppers into the rain channel in between the wing mount/trunk and the body of the car to nearly eliminate the vibration at speed.
There is enough downforce that my trunk (with dual trunk lifts) eventually sticks closed.

 

I lol'd.

I've been there. I've installed a part and I think it did something, but it could be in my mind, and I can't say how much it did.

 

Looks like these guys in the UK ripped off the BBFW spoiler. Since BBFW doesn't sell complete kits anymore, it could be a good option. Looks like about $250 after shopping to the US.

https://agrfabrications.com/products/mx5-lexan-spoiler

 

I'm gonna bump this thread with my attempt to find a discreet, visually appealing, adjustable bump in downforce. With VIR now basically my home track, high speed stability has become a greater concern. Two years ago I had this idea and it's finally on my car this spring.

This was the original concept, inspired by C7 Corvettes and your local Mopar Club / Takeover crews favorite bolt on spoilers. The basis of this is a CarbonMiata fiberglass spoiler.



With the miracle of 3d printed tools, I drilled holes in the fiberglass and installed these Rotaloc adhesive mount nuts on the inside of the spoiler.



I bonded it on to the trunk lid with 3M mounting tape, which I believe to be some variation of their standard VHB line. The CarbonMiata spoiler is not a perfect match to the trunklid, so there has been a bit of separation and tearing of the 3M tape, but it's pretty darn good for the price I pad. Maaco did a great job painting it for $100.35.

For now, I only have hardware in the holes to keep out dirt. I put rubber washers under the bolts and washers to protect the fresh paint.



Here's a profile view of it in action.



I have not experimented with it enough to say if the downforce bump of the spoiler alone is doing much, as I've realigned my car twice since I was last on track in 2024. The spoiler is about 2" high as is, and the wind tunnel testing I've seen from Occam's Racer says it should have some effect.

My next step is to find a cheap source of plexiglass or some other material to make the adjustable blades, without buying a full 4'x8' sheet. If needed for taller heights, I'll also add support rods like the BBFW adjustable unit. Hopefully this will be successful enough for me to look into a front splitter or undertray to cut drag and get some front downforce as well.

 

I'm not sure if I said it ealrier in the thread, but my instability was largely due to a **** alignment. Turn 13 at sebring and the back straight kink at RA were the worst. Post alignment, I can still feel a little 'lightness' for lack of a better way to describe it, but its a 3 out of 10 instead of 8 out of 10 feeling. I really haven't been using my turbo to the fullest at track, so i have a feeling as I turn up boost and speeds, I'll start to increase that instability feeling and need to add a spoiler/wing. I was hoping to find something that was easy to put on/take off in-between track days. For now I gave up.

 

I got tired of tooling around on the streets with a wing, so i went with this AGM fab spoiler (BBFW ripoff). It's honesly a thicker plexiglass and higher quality kit than the BBFW I've seen though, so I'm not complaining. 4 bolts to remove the trunk and swap to a clean look, that coupled with my quick release splitter mounts and the car can go from street car to time attack beast in about 15 mins.




I'm still excited to see what @OptionXIII comes up with.

 

My spoiler made a nice difference at high speed.

Make sure you have 1/4 inch of rake no matter the alignment. It helps also.