Home made splitter/air dam/ducting
 

Threw this together last week. Mostly home depot parts, cost around $100 total.

https://www.miataturbo.net/attachmen...ine=1315443451

I used 1/2" Birch plywood for the splitter, which is overkill. 5/16", 3/8", or Alumalite would be better... but I did a nose slide across the inside curb of a turn last weekend and it held up just fine. My hardware could use improving as well. Its just stuff I dug up at home depot, which means its overweight and poorly suited to the application, but it works for now.

The spoiler is mounted with two turnbuckles in front, one turnbuckle on each side (in front of each wheel, behind the air dam), and two bolts to the subframe in the rear. It extends back to the centerline of the front wheels (as far as legal) where it meets the subframe, creating as smooth of an undertray as possible.

The radiator ducting is aluminum flashing (very thin) held together with pop rivets and attached the the air dam with aluminum angle iron. It's sealed around the edges and attached the the radiator with aluminum duct tape, which wasn't strong enough. I think I'm going to make a frame around the radiator with aluminum angle iron, rivet the flashing to the frame, and seal the frame against the radiator with weather stripping. That will have the added benefit of making the ducting and/or radiator removable without re-doing a tape job every time. Other than the radiator seal I'm very happy with the flashing. I doubt you could find a lighter solution, and its pretty strong once Its all riveted together.

I used 1/4" ABS for the air dam. Its light, easy to work with, and stronger than the bumper it replaced.

Nice job! Looks mean and has smooth sides for canards if you wanted to add them too. Now you can add a diffuser and wing to complete the aero functionality. How high is the lip from the ground?

bring out the gimp.

I'd put sort of extractor vent over the hole in the hood to pull air out better or just put a stock hood back on if I were you. Seems like that gaping hole would create a lot of turbulence.

That is fucking awesome.

Very nice. MOAR PICS!!!!!!!!!!!

any pics you have of the back side of the new cap off the car would be cool, pics of attachment points, etc

just so you know, I have every intention of copying this

They sell the ABS for the airdam at home depot as well?

That looks pretty bad-ass! :bowdown: I'd love to see the backside off the car or from underneath or in the wheel wells.
-h

Looks good. Can it get on a trailer like that?

I cut a similar hole in the hood of my Civic. My oil and water temps went up, and I had no discernible "by the touch" change in underhood temps (didn't bother to measure as it wasn't what I was going for). My assumption is that I disturbed airflow through the radiator/oil cooler by creating a high pressure area right there behind the radiator. +1 for the suggestion of altering that a bit.

:werd:

:eek3dance

Excellent work, I used thin aluminum sheets (not flashing) from home depot on my first radiator duct and it worked great, just took forever to get it shaped and a perfect seal.

This time I'm trying roofing tarp for a quicker install, it's semi-flexible, mostly smooth and heat-resistant. I blocked off the sides of the radiator in about 1/10th the time as using aluminum, even though I don't think it's quite as good a seal. But I just want to get it "close enough" to test and see if I need a bigger radiator anyway, which will probably require me to redo it.

My last splitter from Home depot was posterboard on top epoxied to a layer of thin aluminum on the bottom. Cost a little more than yours but it reminds me of a surfboard, light and stiff. Probably cost about $60 including paint and some fasteners. Worked great on the track, I took it off and intend to use it on my new project. My air dam sucked though, yours is infinitely better.

Where did you buy the airdam material at?

Handy Man you should come up to the dyno day in MD in October. I want to check out this in person and get some more pictures.

Thanks guys. The air damn material was purchased at a local sign shop.

I'll be pulling the splitter off to install a new radiator sometime this week, I'll try to snap some more pics when I do.

It sits about 3.5" off the ground. It can get on and off a trailer with some 2x8's to help, but its a pita. I plan to replace the bolts with cotter pins over the winter to make it easily removable.

Larimer & stinkycheese: The hood is temporary. It will be replaced with a proper CF extractor hood (autokonexion?) over the winter.

sam: The flashing was easy in this case because I'm attaching a square hole to a square radiator, so there wasn't any bending or forming required. It just took a few hours with some tin snips, a drill and a rivet gun to make the ducting.

shuiend: if you have someone there who is good at tuning MegaSquirt, I'll be there in an instant!

how much did that ABS slab run you?

Well Braineack and I have been running MS since 07 and we both have a pretty good understanding of how it works. Honestly I think the majority of cars that will be there will be running some sort of MS system.

Here is a link to the thread with more info about the dyno day.

Subscribed. Somebody should copy this and start selling it as a kit.

love it! looks great. i used all the same materials except for the abs sheet. my buddy made it out of aluminum. How is it handling without a wing. did your car understeer alot before you added the splitter? If i even flatten the angle of my wing a little, the back end gets loose and slides all over the place.

Looks Great.

Zed is dead

Looks real similar to the one I built for Spoolin's car last winter. This is going to be the new trend on the track cars. Waiting for someone to angle it forward like a wedge, following the angle off the top part of the bumper.


Because racecar
http://inlinethumb45.webshots.com/47...600x600Q85.jpg

Make the front and rear longer and pointier, add a Fastback HT:
https://www.miataturbo.net/attachmen...ine=1315565952

:D

Making the front (including the splitter) longer (1 foot or so) will give a lot higher probability for curb interaction (and aerodynamic pitch pumping).
But why not try, it's just plywood, alu and plastic sheets.

I was able to find 8x4 sheets of 1/4" ABS locally for $35 and 1/2" for $75. just to give you a ball park.

I really, really like this splitter/bumper. Very nice work. Cheap, looks good considering, and most of all functional. Awesome.

Excellent idea. This guy who is local to me did the same sort of thing on his track Miata (V8 conversion). Look down towards the bottom of the thread.
http://forum.miata.net/vb/showthread.php?t=424672

My splitter is very similar to yours except for the vertical air dam. I considered that approach once before and chickened out. But now that I have seen it, I REALLY want to do it now. It looks like it takes care of covering up the front tires when viewed from the front. Can you post a front-on picture? It also looks like adding cutouts for things like brake ducting and tow hooks would be easy.

I would not worry about the Home Depot hardware unless you just want to upgrade it for looks. I have been using the same stuff for the front braces on mine and it works great. Track tested, no problems.

+1 on getting ABS from a local sign shop. That is what I do.

Alumalite would be nice but I am sticking with birch for my splitter so that when it is inevitably damaged the replacement material will be cheap and readily available.

MORE PICTURES!

I installed a new radiator and re-did the ducting with AL angle iron and weather stripping which worked perfectly.

The air dam covers most of the tires, an inch or so still sticks out with 225 A6's on 15x9 6UL's. To get them completely covered I'd need flare out the fender where the top of the air damn mounts.

more pics coming soon :)

Another option for filling that gap between splitter and nose is trimming down a stock car nose....that's what I did here. They are cheap/durable...and a little more aerodynamic. Two different versions, first was more aesthetically pleasing but second was VERY effective.

The splitter on the first was sheet almuninum, the second was 1/2 birch with single layer of glass top/bottom. Very cheap and DIY. And most important easily reproduced because you will lose it! Well, at least if racing anyway.

Both look good. I like how you used the curve of the nose to blend it to your car.

Speaking of losing the splitter, I'll be racing the 50th Annual Weatherly hill climb next weekend...which includes a jump! I'm sure it will destroy the splitter, and I can't wait! :D

You could add some temporary spacers to raise up the bump stops.

FWIW I am about to do this on my 1994 LS1 track Miata. I have everything I need in hand so I just need to do it.