yes it is

 

hopefully i can keep this front end off of the wall at summit point

 

^would the J's wing be closer to the APR GT200 or 300 ?

 

It is in between. The GTC-300 is freaking huge and the GTC-200 is a little smaller..

Maybe Danny (SecondRound) has a pic of his GTC-300. It looks good, but is BIG compared to the GTC-200

 

My S in last years track trim.... Look out Jeff. I have your

 

I'm running the GTC-300. Pics are posted earlier in the thread:
https://www.s2ki.com/forums/index.php?showt...post&p=11780461

 

Do you really need that much wing with no front aero and what seems to be -2* camber or less in the front?

 

My track trim is barely different visually from street trim , but nevertheless here it is (and in good company):

 

Didn't we already have this discussion?

If it makes you feel better about your wing, then no, I don't need it, your wing is fine.

If you're actually looking for a truthful answer, then I don't know. I don't have any real (non CFD) numbers for any of the S2000 wing choices.

My aeronautical instincts tell me the wing will not go to waste. Even if you were worried about too much downforce on the rear doing something "bad" to the balance of the car (where "bad" simply means more rear grip than you can use given the front grip), a GTC-300 sized wing can produce the same downforce at a small angle of attack as a GTC-200 wing will produce at a high angle of attack. Increasing lift by increasing AoA is the least efficient (drag wise) method.

The CFD data APR sent me for the 300 suggest the wing stalls out around 13 degrees AoA. This is, not surprisingly, the point where the increase in drag with respect to the increase in AoA stops being linear and begins to accelerate. This is also the point where change in downforce actually starts to go negative (there is less downforce at 14 degrees than 13). However, unlike the previously mentioned linear increase in drag, the downforce increase has been decaying with increasing AoA. The point of all this is that the efficiency, measured in lift over drag, decreases at any angle above 0, and total downforce runs into a limit as the wing stalls out.

From an aero perspective, you are better off using a larger wing at a lower AoA. Given no other constraints (which do exist in the real world, like packaging), if your tuning leads you to not run your wing near flat (at least on your fastest track), it follows that you could be using a larger wing. However, from a cost or rules perspective, the answer may be different.

 

Formula, if we did, I forgot. I am vintage afterall. Yes, I was serious. I have used a GTC200 and found that understeer was a problem. To be fair, I was using a Gendron bar and staggerred tires. Yes, I do know that a larger planform is more efficient. My query was geared towards balance of the car.

Thanks for the post, and now back to pictures.