Factory wing

[gosborne]

Can someone tell me the width of the factory wing? I'm guessing either 67" or 72" but, would appreciate if someone could tell me for sure. Thanks!

[eric1h]

IIRC its actually HUGE @ 86" but offhand i cant remember exactly

[Blue Streak 21]

You were very close. My measured 68.5" wide.

[gosborne]

Thanks Jerry for the confirmation.

I was interested because, in addition to needing a nose for the car, I also need wing....


Eric - is it just the angle of the picture or, is your wing postioned higher that the roof line of the car?

[eric1h]

Originally Posted by gosborne

Thanks Jerry for the confirmation.

I was interested because, in addition to needing a nose for the car, I also need wing....


Eric - is it just the angle of the picture or, is your wing postioned higher that the roof line of the car?

Just the angle, it actually sits flush with the roofline

[panozracing]

I was told at the track this weekend by a team who owns several GTS's that our wing is worthless for creating downforce and we should throw them in the trash and get a real wing. Not sure how I feel about that.

[PanozDuke]

Originally Posted by panozracing

I was told at the track this weekend by a team who owns several GTS's that our wing is worthless for creating downforce and we should throw them in the trash and get a real wing. Not sure how I feel about that.

From earlier threads, it seems that a good front splitter (a la Kel) and repositioning the original wing (a la Eric's adjustable mounts) can be significant. In the stock location the wing adds weight and some drag, but little more downforce because it is not in the air flow. Wasn't it Eric who lost a repositioned wing and almost crashed due to a sudden loss of rear down force?

At the Texas Mile last Spring, Al Lamb ran his GTS, SCCA GT2 car, with and without the wing. He hit the rev limiter both times (168 mph trap), but he hit it 200 yards earlier without the wing and noticed no change in straight line stability. Drag is a factor at high speeds.

Maybe Kel and Eric can restate their experiences concerning splitters and repositioned wings vs. the original air dam and wing location under track conditions.

In SCCA the dam and wing must be as delivered. Other series probably have greater latitude.

Mike

[NZGTRA17]

As much as I would like to categorically state/confirm that raising the wing and adding the splitter have reduced lap times by X amount each, it is difficult for me to do so. I did post feedback at the time providing estimated improvements but have not recorded this in my running log so cannot break out again at this stage.

You all know the old racing cardinal rule of making one change at a time........ Unfortunately reality of time pressures dictated that I had to make several changes at once to get the car ready for the last endurance season.

What I can say is that we started out with a car that was being pushed to the limit (resulting in several off track excursions and broken plastic air dams......) to do 1.12 - 1.13 lap times at my local circuit on a mix of DOT's and slicks. The engine/chassis and aero changes combined to reduce these times to comfortable 1.07 - 1.08's with the car being absolutely stable and predictable. We were able to race mainly in the 1.08 - 1.09 bracket for 6 hours with no drama's for the 3 drivers. The car responded positively to all aero changes made and nothing was changed back as a result.

I am planning future aero mods, the first being a gurney flap for the wing for running in the wet. This has been made and (drag) tested but not run as all running has been in the dry so far. The gurney flap did not impact straightline speed that we could detect. Second aero mod will be lowering the splitter and changing its angle of attack. I expect this to significantly enhance the splitters performance. Lastly we are looking at adding a diffuser to the rear of the car. No development work has been done on this as yet and it is unlikely that it will be ready for this season but research is under way.

Kel.

[eric1h]

I would argue that the wing is WORTHLESS, but I will agree thats it's a high drag low downforce design. I have run some basic 2D CFD tests on the height, and angle of the spoiler to get some basic data, I have real world wind tunnel tested it but the design is a basic reverse "air plane wing" and does create downforce...

Here is a quick graphic of some of the CFD tests I've done. Once the LSx Swap is done my next "mod" is a more productive wing design

Sorry for the large pic But if you look REALLLLLLLY close, you can see the pressure difference just above the spoiler in the right side pics...

[eric1h]

Ohhh, and yes, I had the best possible "real world test" My wings bolts sheered off at 120mph on the uphill S's at VIR, and it was easy to feel the difference the lack of spoiler made through the highspeed winding turns..

[NZGTRA17]

I guess what you are saying Eric, is that when raised up the factory wing does produce downforce (amount unknown) but there are more efficient designs out there (from a downforce Vs drag perspective)?

Have you seen a design that you think would be a good fit for our cars?

There are a couple of wings commonly used out here by other endurance competitors on high powered cars. I will pay more attention to these and get a photo and brand to post.

Kel.

[panozracing]

Guys, when we moved the wing and added a splitter we did notice the added downforce. I think the other teams was pushing that our wing is junk and we should buy a comp coupe or cup car wing (I think we need a larger wing) and bolt that on for some real aero.

[eric1h]

I actually really like the APR GTC-500, I had the GTC-300 on my BMW and it had MASSIVE downforce, and very low drag. my top speeds were only 1-2mph different MAX at the end of the long straights at VIR and the grip level was amazing....

The rear of the car has 900lb spring and its squating down a good 1-1.5"

[eric1h]

Here is some CFD data for the GTC-500...

Its a good length @ 70"

http://www.aprperformance.com/index....sk=view&id=182

I worked pretty closely with APR on the GTC-300 design for the BMW, great guys to work with

[Panoz26]

thats a big passenger in there - looks like Graham. LOL