Vertically along the rear edge of the cut is the only place that makes sense to me. With the flap on the exterior, in the airstream.

 

Maybe. Need tuft tests at a minimum to know. Air passing the front wheel well is probably pretty turbulent, so I'd expect it to be a marginal aid at best.
Now if only I can find a gap in repairing stuff that breaks on my car so I can play with aero again... have a few gurney flaps I'd like to add to things

 

This is what I was thinking. I'm still no fluid dynamics or aero expert.

 

The totally unreliable chocolate-chip-cookie-fueled CFD farm I keep in my buttocks says a gurney flap there wouldn't make a noticeable difference in lap times for our peasant-mobiles. But maybe it's wrong.

Tucking the edge of the fender behind the wheel seems to work well. This bone-stock 1900lb 1.6 is a hair faster around PIR than my car (1.33.5 vs 1.34.1). Takes more power than I have to make up a 700lb difference.

 

I don't see a gurney flap making any noticeable difference there but I don't see why it couldn't help slightly.

 

Going to Sonoma this weekend to try this one out

Moti

 

And the brothers said ... "Hmm"

 

That's cool. A front wing makes a lot of sense when you have a decent wing on the back. Look forward to your results. Remember to try and test all settings on both wings.

 

Shenanigans. I like it.

 

It's hard to balance that big bad NASCAR wing on the back Very interested to see how it works out.

 

Did Targa push a lot at MRSL? (besides the acute oversteer in T9 that last lap ) I took wing out all weekend and couldn't get it balanced.

 

Nope, the car was actually nicely balanced once I had the sway bars set up right. It's got a flat undertray in the nose and a decent splitter. The canards make a noticeable difference as well. Obviously, I needed a lot more wing for that last corner...

Since there have been no pics in the thread. All this stuff is DIY at home. Well, the wing mounts were laser-cut, but since I made the first set at home I'm still taking the points for them
Wing is a COT on FM-style mounts, a bit taller than the production ones.


Canards, splitter and wheel spats. I did do some before/after on the canards, they work.


Splitter without the other bits. The cables allow it to flex up if necessary but they'll take a significant amount of load. I forget the rating, something like 400 lbs each. I also modified the eye bolts to improve their rating.


Under the nose with the splitter removed.




You can tell the splitter's working, the cables are taut! They've got a bit of slack at rest.

 

In regards to the movable aero, I think the more effective and SAFER idea would be to make a Chaparral style movable wing. You can test and tune to find the ideal AOA for low CoD. Then you T&T to find the AOA for lowering lap times. Drive with the wing in downforce mode as the default setting and have the momentary switch hand operated to change it to slippery mode for the straights. This way the wing doesn't go through an unpredictable sweep going through stall and you aren't stuck with it activating if you don't want it to (like if it was on the pedals).

 

You could use one of the radio buttons on the wheel for this. I agree that setup would be safer than the having the wing change attitude through some automated process.

 

My feeble attempt at aero, and with much help from the guys on this thread. 87 RX7, 383 SBC with Holley HP EFI (just finished conversion from carb, tune is in the ballpark but still rough).

Heat is tough for me to keep down, so for now, splitter is tegris off a COT, and does not have a flat underpanel. ABS air damn much like the others in this thread. ABS radiator duct sealed off to the radiator.

Out back, COT wing with adjustable struts. You can make radical changes by moving bolt holes, make slight changes in AOA using the rear struts, or turn both the front and rear struts to raise/lower the entire wing slightly. The struts that angle to the sides do a surprisingly good job at keeping the thing from wiggling back and forth, only movement is the play in the heims and the quick release pins on the angled struts (can't open the hatch without them removed).

Fenders are hacked up factory ones with ABS "stuff" on it. Rules require that you can't see the frame/unibody, so I have a filler piece that sort of follows the wheel contour, and then an ABS scoop behind the wheel. Only real reason for doing it was to clear the 275/40/17's NT01's. I would have just gone shorter, but for budget reasons, I wanted to be able to swap the tires front to rear for the time being.

On the agenda for next year is a tube front end (forward of strut towers), splitter that extends back further, DIY fiberglass nose and fenders, and a rear diffuser/bumper trim. The rear wheel well and gas tank need to be removed and a fuel cell put in place before that happens.

I know ride height is up there (approx 4 - 4.5" front bottom of splitter), but I run hillclimb events on public roads and can't go any lower for the most part. I'm PRAYING my Ground Control/Koni setup shows up in time to make my race in two weeks, but I can probably lower them if needed to run TGPR, Road Atlanta, Barber, or CMP as necessary.

 

Love it Supe. I'm very jealous that you've got hill climb events near you - I don't think there's anything in CA.

I like your fenders. Hmm I wonder why... Mine:

 

Yep, the pics you PM'd me a while back were a big inspiration! It's sitting on the trailer now to have the diff swapped/adjustable toe/camber links/rear steer eliminators by Estus up at E-Speed in Kannapolis (current diff whines like a 10-71 blower), hopefully this thing will actually work worth a **** sooner or later! I removed the factory headlights and put some rectangular Hellas in the driving light holes, so now it looks like a Miata's fatter brother. That counts, right?

Lots of unknowns this time around though, completely new suspension, new wheels/tires/track width, and all the aero stuff is first time out. So, the next hillclimb will be a WAG on all the settings, but it can't be any worse than last year (alternator failed, carb kept flooding, and cut a front tire on a turn, so I had to run a 10" A6 out back and a 215 NANKING radial up front. Needless to say, I couldn't turn much, never mind at any real speed...

 

Just as a follow-up here - the car got finished in time. BARELY.

The end result of the suspension and aero changes was 25 seconds off my time from last year. That's 16% faster, with probably another 15%-20% to go if I had time to dial in the car more and get more comfortable with staying on the throttle through some of the less aggressive turns (got a little overzealous on Sunday, went flat footed into a patch of gravel, and pulled a 1080, missing the guard rail by the nearest of margins...)

The COT wing setup has the *** PLANTED. So much so, that it was inducing understeer through all of the turns, especially on the sweepers. This is at the "neutral" setting where the top of the end plates are parallel with the ground. The rear tires just kept going while the fronts were howling for mercy. And this is with the air dam and a hefty sized COT splitter. I am going to try a plywood splitter with spill plates at the August race to see how it compares, and am going to keep this setup to try at flat track events.

Also, the air dam/radiator box combo was MASSIVELY effective from a cooling perspective. With the stock bumper setup, I had difficulty keeping the car below 220°F. This year, very similar ambient temperatures, 180°F max at the top of the hill, 155°F at idle all day long.

 

That sounds awesome that you were able to shave 25 secs off of your best.

My goal out at Sebring International is 2:20.???, where as a Spec Miata normally runs about a 2:40.000.

Sadly yes on most cars it is hard to make alot of front downforce with a simple air dam and splitter. I want to make as much downforce with the front then compensate with the rear.

Keep up the work!!!

 

I think the next version of my ep style front end will have have a canard setup similar to Nicks car



thoughts on this? im looking for more front end down force to go with my COT wing. i already have a gt500 vent in the hood so im running out of options for less lift/more down force in the front