Another DIY splitter/air dam installation
 

So though I had considered doing something like this before, I was not ready to take the plunge until I saw Handy_Man's installation on this thread...

https://www.miataturbo.net/race-prep-75/home-made-splitter-air-dam-ducting-60291/

I really like the way his turned out so I decided right there to use the same approach to remake the splitter and air dam for my car. The splitter is made from 3/8" birch plywood, which I had left over from the first splitter I had made. The front air dam is made from 1/8" black ABS purchased from my usual supplier, a local sign shop. The ducting is made from black coroplast, also from the same sign shop.

Here is the finished result...


The new splitter with a hammer shown for scale.
https://lh5.googleusercontent.com/--...2/PB120043.JPG


Front view
https://lh3.googleusercontent.com/-y...0/PB200062.JPG


Ducting is visible on the sides inside of the dam, and around the oil cooler
https://lh5.googleusercontent.com/-7...2/PB200064.JPG


Small holes on the sides are for the brake ducts
https://lh4.googleusercontent.com/-u...2/PB200065.JPG


Inside the right side wheel well
https://lh3.googleusercontent.com/-2...0/PB200066.JPG


The splitter from underneath
https://lh4.googleusercontent.com/-v...0/PB200068.JPG


Miataturboz needs moar dogz, fast onez.
https://lh6.googleusercontent.com/-3...2/PB120046.JPG


Canards and kitties to be added later.

Dude, I love it! That's gonna work wonders for the front aero. May have to give that a try over the winter months

Very nice!! Moar pics :bigtu:

looks great. i may have to search for some of that abs around here. wasn't able to find any last time, may dig a little deeper.

Thanks I am happy with how it turned out. With canards it should look better still. When I get it back on the ground I'll take some more pictures.

Spoolin, keep trying. There should be some places where you are at that sell it, like the sign shops. They might not know WTF ABS is since it is not something they would normally use, but if you talk them through it I'll bet they can order it from their normal plastics supplier. I went through this the first time.

If not, let me know and I can buy you a sheet and bring it to TWS. It is about $75 for a 1/8" x 4' x 8' sheet.

I've looked at alot of these front splitter threads, and no one that saw mentions what the turnbunkles are mounted to on the car? Are you drilling and taping a hole, welding a nut on, or is it a pre-existing threaded hole?

In my case the upper end of the turnbuckles are attached to an existing hole in the bumper via the same carabiner hooks you can see at the splitter end of the turnbuckle.

This is happening to my car this winter too - thanks for starting another thread. What did you use for the little 'L' brackets mounted to the splitter in the first picture? I was going to just slice up pieces of aluminum angle but what you did looks better/easier/lighter.
-h

It is garden edging from Lowe's 'Racing Supply'. Cheap and effective FTMFW

That looks super effective, very similar to Spoolins. Get ready to tune the rear grip because you just increased the front a butt load :)

This year the flat front is the new hottness, next year...

Looks even better in person!

This is exactly what I have planned for my car.

Was your main goal drag and lift reduction vs. downforce?

When you understand this equation you will get it.

L > <

Lift reduction = net downforce. That's what splitters and diffusers do with negligible drag. Wings and canards make downforce but add drag in proportion to downforce.

Yep what Spoolin said.

Positive pressure on the top side of the splitter that sticks out forward of the airdam will also make downforce.

[IMG]https://www.miataturbo.net/attachmen...0&d=1322497651[/IMG]

The testing at the race track was successful. Here it is in action at Texas World Speedway on the NASCAR banking in Turns 3 and 4. I set my personal best lap time, about 1.5 seconds faster. There were a lot of other variables so I cannot attribute all of the speed to the new splitter and air dam. But they were definitely working. The aero balance of the car was great everywhere.

That turn 3-4 session was crazy.

Stupid fast! We all had a good time trying it out.

Whoa! You guys ran 3+4? You must have been flying in to 1....awesome!

So I'm researching splitters and came across this thread. The air dam looks great and more importantly, looks functional.

So questions.

Is the ABS air dam just riveted/bolted to the stock bumper?

Is there anything supporting the bottom of the air dam besides being connected to the splitter?

It is riveted to the upper section of the stock bumper. The lower section of the bumper has been cut off.

The splitter is supported by separate structures bolted to the frame and the two turnbuckles visible in the front.

Cool thanks. Trying to get this done before the new time trial season starts in mid January.

I didn't think about how horrible the stock Miata's aero is until we did Firebird Main here. It uses the drag strip as part of the road course so there is a half mile straight. There is an NSX in my class that has ~15 less whp and about 400-500 more lbs, but he's going about 10 mph more than I am by the end of that half mile. Might be gearing also, but I'm sure this will help quite a bit.

a little of that could be do to corner exit speed difference. especially considering the fact that he has a mid engine car with alot wider rubber. But yes, miata's aren't very aerodynamic. Anyway, just wondered, what's your comp weight? (car+driver) that puts you in TTA with 251whp. And is that your reclass by greg g, or you up to TTA in points from TTB?

The options Greg gave me were TTA* I could do 235whp at 2160lb or 262whp at 2338lbs. He gave me a TTB** option of 235whp at 2440lbs, but doesn't make any sense to do that one due to the base tire size points refund. The difference between running TTB** and TTA* is five points with the change in base class tire size when running 225s, so basically 5 points is buying me 27hp and about 100lb lighter. Points breakdown is
-19 for 225s, +7 NT01s, +3 6 speed, +3 LSD, +3 shocks, +2 springs, +2 sway bars, +3 air dam, +3 splitter, +4 wing, +7 for *.

So 18 points into TTA. I ran this last year with a 5 speed, no aero, and old suspension. Just had all that budgeted beforehand when I picked my class, except the 6 speed. I blew my second 5 speed this year at the Dec event, so decided to not do canards and diffuser to have a better chance at not losing another transmission. Added the 6 speed, XIDA-S, APR GTC200 wing this month so far. Just need to build that front air dam/splitter and setup the suspension height/corner balance before mid Jan.

My last comp weight was 2400 with 3/4 gas. I'll be gutting the doors and exercising to get that last 50ish lbs out of the car to get near the limit.

That's the 1st I've heard of him giving an option to base-class a miata in TTA - all the points adders, this is why I'm just going to run TTS and suck it up.

Figure I'll just tack this on here instead of creating a new thread. Thanks to ZX-Tex and Handy Man on how to do the front end. Also thanks the BBundy on his idea on mounting a universal GTC-200.

So first off, I have never really tried to fabricate anything like this. I've only done bolt on type stuff. It's been ages since I've worked with wood, and this is my first attempt at using fiberglass resin so the finish came out pretty crappy. It should be mostly functional still :rofl:

https://www.miataturbo.net/attachmen...ine=1326516088

https://www.miataturbo.net/attachmen...ine=1326516088

https://www.miataturbo.net/attachmen...ine=1326516088

The splitter is 1/2" birch, couldn't find 3/8 around here. The bumper is 1/8" abs plastic.

I couldn't find any L shaped garden edging at the local Lowes and Home Depot, so I used garage door weatherstripping to try to seal the bottom edge. Connecting the abs to the splitter I used Dzus fasteners. The top is just 3/16" rivets.

Many people use splats or canards to try to cover up the exposed tire on the sides. I'm points limited for TT, so I flared the abs out some to cover the tires. Just put two L brackets together and rivited it. It is about 2.5 inches out on each side.

These pictures are test fitting after I did the fiberglass. For some reason the driver's side is hanging a little lower than before. It is just a little over 3.5" off the ground. The backside is mounted to the steering rack on a second smaller piece.

The wing is mounted using BBundy's method. I only have single risers, and the stock wing is a single piece all the way across which prevented me from opening the trunk with the APR installed. I removed the hinges and installed hood pins to the front corners of the trunk, and it still uses the stock latch on the back.

https://www.miataturbo.net/attachmen...ine=1326516088

https://www.miataturbo.net/attachmen...ine=1326516088

Still more stuff to do, but the next event is tomorrow so ran out of time to make it look pretty.

Looks really good

Does anyone have the general measurements of the ABS sheets? Local place only does 4x8..I would need to cut it down to fit in the car.

Just roll it, hold it together with spring clamps, and toss in the passenger seat.

Aero Baby Step
 

I am on a long Aero project. I work really slow. I have really liked this thread. To me step one is giving the air coming through the nose a place to go so you are not a hovercraft. So, here is a DIY hood vent. Time: 30+hr drafting, 6hr install including template construction. I have only completed the driver’s side. Passenger side for another day off. $100 in water jet time.
https://cimg6.ibsrv.net/gimg/www.mia...bd8c7eece.jpeg
https://cimg4.ibsrv.net/gimg/www.mia...d4f16e144.jpeg
https://cimg5.ibsrv.net/gimg/www.mia...e49a76363.jpeg