I would love to have a carbon fibrè flat bottom. That said I have no way of paying for one. So while I would love it if you made it I wouldn't buy one for awhile... unless say bit was under 200 bucks then I'd buy a few for me and the cars I'd potentially buy in the future...

I was looking at making some carbon fiber parts with my roommate who semi knows that stuff. (I've personally only made a few fiberglass sub boxes my self and repaired fiberglass)

 

nevermind

 

I agree with you though. I picked up and shipped a diff for a guy for 30bucks profit for me and maybe an hour of my time. Time is what I've got lots of money not so much. But also I enjoy tinkering and learning stuff so even if I could buy something I'd probably rather get dirty and make it my self if I could do it almost as well for cheaper.

 

So one guy wants his diffuser "cheap as ****", and the other guy wants it made from carbon fiber, which given that it's going on (I assume) a street legal car is the definition of wasting money. Hmmm.

It would be easy to make a carbon or fiberglass flat bottom...by using an aluminum flat bottom as a template. However, it would be susceptible to engine heat. I'd try the first one in fiberglass. And probably the second, and third...

 

I'm going to be learning to drive/doing track days this summer. Should get better mpgs though as a street car. If you've got access to carbon fiber and resin why not just use it idk the price of aluminium but I'd assume its comparable

 

 

As what 18PSI said, a piece of aluminium of that size I used would cost about $200-500 depending on size and thickness. If you were to make the underbody out of carbon it would be 2 layer with sandwich core (at least), approx price by yard would be around $450 not including sandwich core, resin or a mould. Fiberglass would be about 1/3 the price of carbon but would crack easy with speed bumps or other high section of road.

 

If you were to make it, aluminum is your best bet. It's relatively cheap, and if you dent it, you can possibly knock it straight with some persuasion. You hit something with a cf or fiberglass piece, it'll more than likely crack, and it's not as easy to fix.
As far as weight is concerned, it is on the bottom of the car. The very bottom. And the weight will be dispersed amongst the 4 corners. It's really not a big deal. The aerodynamic advantage will more than likely outweigh the weight penalty. Especially on cars that are primarily driven on the street.

Cordycord, what would be your method for mounting your under-tray? I'm curious.

 

Agree 100% with your comments. But I'm sure I'll make a composite floor when I go for my "Time Attack" car, which will go for all-out weight loss.

The Catfish has it's outer panels mounted by pop rivet to the tubes, and the center tunnel mounted via inset quarter turn fasteners. The floors have laser-cut holes that line up perfectly with the tubes. All that's needed is to place the floor, drill the holes, set the rivets in place and then "pop". The floor goes on in less than 20 minutes.

I've worked out the fitment for the Catfish, but that translates to about 75% of the solution for a Miata. Still, I think it would be neat to be able to buy a pre-cut floor kit--complete with laser cut pop rivet holes that you could put on your car in less than an hour. Easy PZ, but no way "cheap as ****".

 

Mine isn't that simple to jack up, but when I get back from Florida for 2 months I am going to solve that problem by drilling holes for jack pad inserts under the car. Then also I will be working on a undertray that is separate piece than the splitter.

 

I am interested in knowing more about a potential flat underbody kit. Not everybody here is a broke-*** college student, but I feel pretty confident in saying that almost everybody here is interested in using their budgeted funds effectively, whatever that budget may be.

• How does the car get jacked with it on
  
• Ease of removal/installation for maintenance access
  
• Durability
  
• Cost
  
• Ground clearance impact

Etc. Answers to these questions determine whether the market is dedicated track-only cars or can be expanded to include dual purpose cars.

 

Stop making so much sense Mobius...

In for pics and pricing...

 

Here it is:

splitter/front
left/center/right main body
rear diffuser
assorted mounting hardware

Jack points don't need to be difficult, just thought out. Long story short, sandwich material under and over the underbody so it doesn't buckle, and so the jack doesn't walk. Without going into too much detail, easy peazy.

I took dimensions last week, and could probably have something ready to laser cut as early as next week, if I weren't so damn busy putting the Catfish together, I could have the diffuser and main underbody done next week. Heat management, mounting points and diffuser outline are all that are needed.

 

Sell the sections individually, more people would probably be interested in the front piece.

 

Hey "cordycord" is your undertray just to fit under the engine or is it also a splitter also. The resin I'm asking is because, I'm going to finish my underbody when I get back and I'm going to have the front section in 3 pieces. The front undertray, a 3" airdam and the splitter. What thickness are you running on the undertray, because I was thinking of using Alumalite for it.

 

Right ... there has to be somewhere to jack the car, and then also somewhere to put the car onto either jackstands or to put the lift supports (for those so fortunate) that do not involve the underbody so that it may be installed/removed.

Spinning my car on a rotisserie to install & remove my underbody is not currently within the scope of Ms Mobius-approved budget levels

 

I don't think anything developed for the catfish is going to transfer over to a miata with anything less than pretty much a total redesign.

 

Wrc style jack points. Another retarded thing I always wanted to do

 

What ? Air piston jacks. I was thinking of doing the same thing with only 3 jack points.

 

not air piston jacks. WRC cars have reinforced cylindrical holes in the sides and their jacks have pins that insert into them.