For the S197 Mustang platform, proven aero does not have to be expensive. We install a wind tunnel-tested Steeda wing and a BOSS 302 splitter to improve the downforce of our car.
The Steeda wing was actually the spec-wing for the Ford FR500C and BOSS 302R race cars that raced in the Grand-Am GS class between 2005-2015. I won a lot of races in the No.61 BOSS 302R driving with Jack Roush Jr. for Roush Performance. While at Roush, we had this car in the Lockheed Martin wind tunnel and it was eye-opening to see this $350 wing produce hundreds of pounds of downforce.
The Ford BOSS 302 splitter is a mild but worthwhile improvement over the bare GT front bumper. For the money, it improves the airflow around the front bumper, lowers the front fascia a little over an inch, and creates a protrusion in front of the bumper that creates a high-pressure area and a little downforce. For the money and ease of installation, this is a simple must-have for tracked 2013-14 cars.
The stock 2013-14 Mustang front bumper design was influenced by the 2010 Shelby GT500. Personally, I really like the looks of this bumper ever since we had pre-production versions on our BOSS 302R race cars.
Without a splitter of any kind, the car just doesn’t look as aggressive as our race car and creates more lift. We are about to change that.
Out back, the stock GT spoiler is tiny and while it does reduce drag and lift, it’s not enough to feel it.
The BOSS 302 splitter comes in 2 pieces. The flat under-panel as well as the exterior protruding lip.
Quick Reference:
Page 1 – Overview
Page 2 – Boss Splitter Install
Page 3 – Installed Boss Splitter Review
Page 4 – Remove Stock Spoiler
Page 5 – Clean Decklid & 3D printed Adapter
Page 6 – Mount Steeda Wing
Page 7 – Review and Aero Insight
10 comments
Tape redidue comes off with a caramel wheel. No blisters necessary.
Another good Billy Johnson article. If the used car market wasn’t so insane, I would be all over a ’13-14 Mustang and follow all your advice to modify it. I have only ever had miatas on track, so some power would be a nice change.
Thank you much!
Billy, for Part 6, what considerations to you make for aero when selecting the Steeda springs for the car?
Based off of the goals for the project to be a budget track car that’s also driven on the street without beating you up, and from my experience racing the S197 (with this aero) the Steeda spring and bar rates were chosen accordingly. Stay tuned for when I track test and evaluate this setup!
Great articles, Billy! I can’t believe I came across this one just as I am trying to reproduce the aero package of the GS cars ever since I saw them at COTA in 2013. Most people like the WC cars, but I have a heart for endurance racing and I always wanted to duplicate the 302R. Anyway, I bought the Steeda wing years ago, but am only just now getting around to figuring out the mounting “shim.” I have contacted many of the race builders and nobody seems to have any left in a box on a shelf somewhere. I thought it would be awesome if somebody could just 3D print them and now – you have gone and done just that! Uh, any chance you can share that file? Any help would be appreciated. My website link goes to my write-up of the 2013 COTA race with a couple of pretty good pictures of your car.
Would be even nicer if Billy could print up a half dozen or so of these at a time and make them available to purchase cor those of us with no 3D printing abilities.
That could be arranged.
What is the part# of the Steeda wing you used? I looked on Steeda’s website and did not see this wing. They may not have the correct photo posted.
The 3D printed adapters would be slick.
Thanks
I am getting ready to do the same things to my 2006 Mustang GT. Please let me know if you have the adapters available. Thanks for the article!