Who has made a RACING air dam for the protege third gen???

[sm76]

Wouldn't the increase in frontal area negate any gains in terms of overall efficiency? I thought that was a huge part of the reason those long distance electric racers look like this:

and not like this:



(shrug)

Look at the bottom of those solar cars, it is smooth and allows air to flow over it easily. Now think of what the bottom of a car looks like. There are suspension pieces, drivetrain, exhaust, rear bumper, etc. hanging down in the flow path. The air dam increases drag at the front of the car by an amount, but the air dam decreases the drag under the car by an amount +1 so the overall effect is positive. If you had a full undercar tray, that ratio would probably flip.

 

[aMaff]

Look at the bottom of those solar cars, it is smooth and allows air to flow over it easily. Now think of what the bottom of a car looks like. There are suspension pieces, drivetrain, exhaust, rear bumper, etc. hanging down in the flow path. The air dam increases drag at the front of the car by an amount, but the air dam decreases the drag under the car by an amount +1 so the overall effect is positive. If you had a full undercar tray, that ratio would probably flip.

Fair enough. I'm no aero expert, it just seemed counter intuitive

That article is pretty interesting, thanks for sharing it (thumb)

 

[iracemine]

So in my continued research I find only more people using what I already have used. Home depot garden edging.

I guess this time I will add the diffuser along with the 1/4 turn fasteners as one piece. Hoping that the dam will now be very sturdy on its own, and light. Along with possibly raising the low pressure behind my P5, and some few more extra hp my build thread http://www.mazdas247.com/forum/showthread.php?123823894-iracemine-s-purpose-built-N-A-ST2-thread I am trying to get around only one more car.

Pics to come later as I need the motor in the car to make the diffuser around the new header.

 

[sm76]

So in my continued research I find only more people using what I already have used. Home depot garden edging.

I guess this time I will add the diffuser along with the 1/4 turn fasteners as one piece. Hoping that the dam will now be very sturdy on its own, and light. Along with possibly raising the low pressure behind my P5, and some few more extra hp my build thread http://www.mazdas247.com/forum/showthread.php?123823894-iracemine-s-purpose-built-N-A-ST2-thread I am trying to get around only one more car.

Pics to come later as I need the motor in the car to make the diffuser around the new header.

Mine is also garden edging, but it is fiberglass and is pretty stiff. 100x better than the plastic stuff. I think I got it at Lowes.

 

[iracemine]

cool got it! http://www.lowes.com/pd_328664-304-...gps-_-gps-_-gps-_-3355614&CAWELAID=1367993885

Had a bunch of large thick extremely stiff and light cardboard billboards. However they are not long/wide enough to make it across the front of the car. So I have a feeling no matter how I would get them to stick together they would be weak. So I am now trying to find a 1/8" sheet of mdf or some other hardwood. Not as light but a bit easier to work with and less water damageable.

 

[Protege2886]

Between this thread and reading Bill's old build thread, I'm getting the itch to go make some aero bits.

 

[njaremka]

yeah, this thread makes me want to create something to improve the front of our mazda5... i'll probably wait for my miata to come in

 

[Protege2886]

Has anyone thought of using corrugated plastic in a sandwich between thin plywood or 22 ag sheet metal?
I know that a lot of people have used plywood, MDF, and plastic sheets all on their own but I've been reading up on corrugated plastic. I have friends who have used the thinner sheets to fab up templates for FG flares and air dams. Now that I've started looking into it, I'm wondering if I could use the thicker stuff in combination with either sheet metal or plywood to make a splitter/undertray.

My only concern would be the "crush" strength of the plastic. The top layer of metal or wood would bear all the force with minimal force applied to the lower piece of metal/wood but I imagine there may still be some compression.

The sheets are available with flutes (ribs) that either run lengthwise or widthwise. I'd choose a sheet with flutes that run in the same direction as the direction of motion of the car (ie run front-to-back not left-to-right) to avoid the plastic creasing at the flute.

10 sheets of 24"x18" plastic total 60$ so I may fab something up.

 

[njaremka]

i've heard of using 3/8" plywood wrapped in fiberglass. i dont know that the corrugated plastic would be rigid enough for an air dam / splitter.

 

[Protege2886]

Hence the sandwich between a thinner plywood. I may try it out and see.

I was just thinking about it a little more and rather than use a single thicker sheet of plastic, I could layer thinner sheets with different flute orientations (a la CF fabrication). You could do a 0x90x0 (0 being in line with the length of the vehicle). Ideally you'd have 45x45x45 pattern but this is plastic sheets

Pardon the chicken scratch. These are just rough thoughts right now.

 

[sm76]

The new popular material is alumacore. It is two pieces of thin aluminum on either side of corrugated plastic. It holds up pretty well.

 

[Protege2886]

So what you're saying is I'm not crazy - awesome (lol)

Thanks Bill!

 

[iracemine]

OK since the weather is getting warmer and the car is with out motor. I have done a bit of research about the rear window. I looks like I will be keeping it glass and instead of making it plastic with cutout holes I will be making air diverters on the b piller and a rear diffuser.

more pics to come.