The Mustang Forum for Track & Racing Enthusiasts

Taking your Mustang to an open track/HPDE event for the first time? Do you race competitively? This forum is for you! Log in to remove most ads.

  • Welcome to the Ford Mustang forum built for owners of the Mustang GT350, BOSS 302, GT500, and all other S550, S197, SN95, Fox Body and older Mustangs set up for open track days, road racing, and/or autocross. Join our forum, interact with others, share your build, and help us strengthen this community!

Wicker Bill and Down Force

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

I have been driving my car on the street more and more and have been feeling self conscious about my giant wing :).

I actually dont mind but I have my stock GT500 trunk and have considered adding a larger wicker bill to it. I know wicker bills inherently create more drag but is there any information out there that shows the down force the create compared to wing, and how tall the bill needs to be to create any functional downforce?
 
i think it's going to be hard because the wickerbill functionality relies heavily on the angle of the spoiler to the chassis and the associated angle of the wickerbill to the spoiler. Some wickerbills are merely extensions of the factory spoiler angle, others alter the angle, and others still (like the 2019+ GT350 and GT500 units are so heavily angled, they're almost closer to gurney flaps than wickerbills.

Without putting your exact scenario into a tunnel or CFD I don't think you can really rely on any data you're going to find as there are simply too many variables in place.

I will say that Ford claims that the 2019+ "swing" on the GT350 and GT500 with the wickerbill in place makes more downforce than the GT350R spoiler, but with a higher drag penalty. GT Gt500 CFTP spoiler makes more downforce than both with less drag than either.
 
i think it's going to be hard because the wickerbill functionality relies heavily on the angle of the spoiler to the chassis and the associated angle of the wickerbill to the spoiler. Some wickerbills are merely extensions of the factory spoiler angle, others alter the angle, and others still (like the 2019+ GT350 and GT500 units are so heavily angled, they're almost closer to gurney flaps than wickerbills.

Without putting your exact scenario into a tunnel or CFD I don't think you can really rely on any data you're going to find as there are simply too many variables in place.

I will say that Ford claims that the 2019+ "swing" on the GT350 and GT500 with the wickerbill in place makes more downforce than the GT350R spoiler, but with a higher drag penalty. GT Gt500 CFTP spoiler makes more downforce than both with less drag than either.

I figured it was not as simple as I wanted it to me. Aero is definitely a weak point in terms of my understanding. I get it as a concept but need help in practice.
 
Home crafted. ABS plastic, similar to boss 302ls but larger. Mounted to the bumper support but not as stiff as CF or Wood.
If you put a big wing in the back without balancing the front the car will run very bad.
Of course you can run the wing at 0deg or negative but what would be the point?
If you not considering a real splitter you may want to go with a smaller wing.
Bigger is not better
Balance is better.
APEX 8 by @AJ Hartman Might be for the moment the best option for you. Nice downforce. Less drag.
I use the fucrum 14. But my splitter is very big and low. And with tunnells
 
Last edited:
If you put a big wing in the back without balancing the front the car will run very bad.
Of course you can run the wing at 0deg or negative but what would be the point?
If you not considering a real splitter you may want to go with a smaller wing.
Bigger is not better
Balance is better.
APEX 8 by @AJ Hartman Might be for the moment the best option for you. Nice downforce. Less drag.
I use the fucrum 14. But my splitter is very big and low. And with tunnells
Lots of good input. In attempt to keep the car functional on the street, I am definitely sacrificing track benefits.
 
6,361
8,182
when folks go down this path, I usually have 2 recomendations, especially for the S197 stuff
Use the IMSA (then Grand Am) spoiler/splitter combo or, if you want a more agressive approach, use the old PWC spoiler/splitter combo. Both of these were developed in a wind tunnel, are balanced, and work.

uOMdpuBl.jpg
mYm8S0il.jpg


xKKY2jJl.jpg

if you cruise around my sn95/ Foxbody posts, you will find the details on making an adjustable whicker bill.
bwrt6VTl.jpg
 
323
316
Exp. Type
Autocross
Exp. Level
20+ Years
So Cal
I have been driving my car on the street more and more and have been feeling self conscious about my giant wing :).

I actually dont mind but I have my stock GT500 trunk and have considered adding a larger wicker bill to it. I know wicker bills inherently create more drag but is there any information out there that shows the down force the create compared to wing, and how tall the bill needs to be to create any functional downforce?

Make a couple taller gurney pieces in 2" height increments. Drag doesn't matter if you're on a track. Just run as much gurney height as it takes for the rear to feel secure. If you add more than just a couple inches in height, then you may need extra supports for the spoiler.

Downforce _ALWAYS_ feels better. The only question is whether you can balance it.
 

TMO Supporting Vendors

Top