Here you go, they come in white or black and flex nicely to the shape of the fender.
Whitecap Nylon Louvered Vents

 

Here is a pic of them KORACING :: High Quality Automotive Parts - Products,click on the pic to enlarge. Don't pay attention to the 3 full car pics as those are old ones from an earlier tune with a different turbo. The bullet mirrors were removed to install the vents and mirrors were installed back on the doors.

 

If the panel is fiberglass, just grab a dremel and cut the slats in it, twist the slats to angle up into a louvered position, then glass the corners to hold the slats in that position. Integrated louvers, no add-on pieces. Fiberglass is flexible.

-Ryan

 

I owned a fiberglass co for 10 yrs in ft laud. and cutting the fiberglass neatly would be hard enough, then twisting it up at an angle would require alot of reglassing underneath to get strength back and then you would have a bunch of finish work to do to make it look nice as the glass fibers would tend to shred loose. For $19 apiece and 5 mins of jig sawing per fender you can have the others installed and they are very functional and look nice.

 

It can be done, didn't say it was easy If you've got a flat panel to work with, sure, buy pre-fabbed. If it's a curve, good luck finding a pre-made louver that will conform to it.

 

That is the cool thing about these vents, they flex as you can see on the stock fender which should have the same curve..

 

My buddy Sean is competing in the Modified class of MC and the series is coming down to the wire, so he asked me what we could do to his car to improve the aero in the rear. I ruled out bigger stuff like a diffuser that would take me multiple days to make, but still think some improvements were made:

We went with redesigned wing endplates (running the square APR/949 units previously) that should increase the efficiency of the wing. This should mean he can run a shallower AOA and probably still get the same net downforce as before, but with much less drag.

Also made dive planes in front of the rear wheels to keep air off the tires.

 

In the conversation about flat underbodys on page 15 it was suggested to extend the tray past the pinch welds to prevent air from being sucked under. Would it make sense to use an underbody that extends past the pinch welds far enough that you create a feed style skirt at the same time? Seems like two birds with one stone.

 

I have the Garage Vary side skirts pictured above and my Flat Underbody goes from side skirt to side skirt.

 

This looks like a fast racecar.

 

That sounds like a good alternative to me, thanks!

 

Hahaha! inorite.

We should all get our aero ideas from hardparkerworld.com.

 

So a rather definitive report on the aero developments I've been making this season..

Last November at Auto Club Speedway (40+ second straight/banked turn) I was nudging 134 mph with 207 whp on the straight and then scrubbed down to ~130 turning into the banked turn.

This weekend I was cracking 140mph on the straight on low boost (~180whp), and keeping my foot in it turning in, not scrubbing any speed and sustaining 140 through the banking. Bumping up to 205-ish whp gained ~2 mph more on the straight, and I scrubbed back down to 140-141 through the turn. (This is all based on gearing calculator)

Tires are BFG Rivals, last December I was on RS-3s; lateral grip is nearly identical between the two, if not slightly in favor of the RS-3.

Everyone blames the turbo for me winning Super Mod, but I had 200+ whp and RS-3s last year and wasn't winning. I'm still on junk coilovers, still running street tires, and some events I've left it on low-boost to conserve the tired 1.6... my primary focus, and where I've spent my hours this season has been the aero. I think the turbo is just easier to point the finger of blame at

-Ryan

 

Congrats on the win. I think the fact that you race like every weekend has something to do with it too. *cough-skill* Don't let the car get all the credit.

 

FTFY

 

FTFM

Compromise

 

I don't get nearly as much seat time as I would like, usually one day per month. Sometimes I get lucky and can make the second day of a weekend happen as well, but it's not common. This past weekend was a treat - got to drive Friday and Saturday.

Emilio is right, big difference between time trial and racing. I'll be making the switch to proper racing soon to take the next step with my driving development Time Trial is Qualifying in racing terms

I do feel my driving has improved since last year, and other factors as well that contributed to a much improved lap time over last year, but for that section of the huge straight, there's few important factors besides aero and horsepower, so looking at that area alone and the significant difference in top speed and cornering speed through the bank, with less power even, it's pretty clear what made that difference.

-Ryan

 

To report after going to the track.
Dollars spent: ~$20(bought the material a few months ago)
Hours spent:3
How effective:3
0=slower, 1, no improvement, 2 =slightly better,3= big improvement
Materials: Dibond knock off from local sign shop.
Tracks tested on: ACS
Race/TT class built for: Miata Challenge Modified class.

Going into this track day the wing stayed at -1.0 degrees relative to the ground plane and I kept the 949 air dam on the car.

There was a MASSIVE improvement in rear down force and reduction in drag. I gained a few more MPH going into T1 & T2 (+5 mph according to gps) which allowed me to maintain 120MPH. In turns 5/6 & the back complex before the front straight away I had a lot more under steer compared to the last time I was at the track. I softened the dampening 1 click on the front shocks and the car regained some balance. I suspect the car could stand to have the dampening softened one more click and it will throttle steer nicely again.

Overall the changes were very worth while.

 

Rokomis, care to post a pic?

 

Edited the post and added a new one, I didn't want to copy and paste the same pictures ThePass posted.