Rob Kinnan
Brand Manager, Mustang Monthly
July 6, 2016
Photos By: Wilwood

It’s nice to know a big aftermarket parts company can get caught up in the same snowball that most of us civilians get stuck in. The snowball we’re referring to is the infamous project car runaway where an idea for a simple, basic hot-rod morphs into a monster that just gets carried away in terms of seriousness and expense.

In Wilwood’s case, the brake manufacturer bought this 1966 Mustang hardtop to develop a four-lug brake kit that would fit into stock 14-inch wheels. He even pulled out the engine and transmission and sold them to a local Mustang owner for his own restoration project. The trunk, floors, rear lower quarter panels, and doors were “rusted beyond repair” in Wilwood’s words. Instead of just throwing the car into a junkyard for scrap, they thankfully, decided to build it into a usable car to develop more products and promote them at car shows and events around the country. They replaced all the body damage using fiberglass front fenders, hood, and bumper, as well as a fiberglass rear deck lid and fender flares molded into the steel rear quarters. Tony Porto and Greg Hyatt did all the body work in the Wilwood R&D shop, then had Paintin’ Place in Westlake Village, California, spray on the retina-burning Viper Red paint.

Those slick rear fender flares are fiberglass parts molded into the stock steel quarter panels. The front fenders are fiberglass parts, as well.
Black anodized Boze wheels just look wicked on this Mustang, especially when combined with the blacked-out chrome parts throughout.

Because pro touring events like the Optima Ultimate Street Car Shootouts are so popular now, the Mustang took a decidedly more aggressive direction. It wasn’t just a platform for a small brake upgrade package, turning into a much more hardcore road racing and track day plaything. A full TCI suspension package is now under the car using the company’s torque arm setup, which is essentially a three-link. The rearend is a Strange 9 inch with 3.95:1 gears and 35-spline axles. The front suspension is also from TCI, using its custom IFS setup that maximizes ground clearance and performance and also gets rid of the stock Mustang’s intrusive shock towers. Ride Tech coilovers and Falken rubber on Boze 18-inch wheels are at all four corners, with 315s on 11-inch wheels in the back, 295s on 10-inchers in front. Of course, the brakes hiding behind those wheels are monstrous Wilwood 14-inch Aero6 binders in front, Superlite 4Rs in back.

The scoop on the fiberglass hood is open, letting cool air in at speed and hot air out the rest of the time.

That shock tower-ectomy was necessary to provide clearance for the wide cam covers of the 5.0L Coyote crate engine. Realizing the car would most likely get beaten on pretty hard during track time, the project managers at Wilwood wisely left the Coyote engine stock for reliability’s sake, but used a set of Doug’s headers, which were prototyped on this car, using 1.785-inch primaries and three-inch collectors, and metallic-ceramic coated.

There are a ton of details on this car that you can explore in the photos and captions. Know that every one of those details is there for a purpose—to go fast on the track and do it in style. Oh yeah, and stop really, really fast!

The Wilwood Workhorse’s interior is fairly Spartan, with Corbeau buckets sitting on a lowered (for headroom) floorpan and on either side of a fabricated transmission tunnel. The transmission is a Tremec six-speed with a Centerforce clutch.
A nod to creature comforts is the Vintage Air A/C system with controls mounted to a billet aluminum plate where the radio normally goes in a Mustang. The gauges were tossed in favor of a programmable Racepak data acquisition dash.
The pedals are Wilwood’s Swing Mount setup (PN 340-11295) that combines the brake and clutch pedal into a single unit with master cylinders mounted in the engine compartment.
The three master cylinders are two for the brakes (5/8-inch rear, 3/4-inch front) and clutch slave (3/4-inch).
The 5.0L crate Coyote was left alone, but fitted with a prototype set of Doug’s headers.
All of the suspension came from Total Cost Involved (TCI). The rear torque arm setup eliminates suspension bind that occurs with leaf springs under hard cornering. As you can see in the detail photo, it uses a telescoping slider at the front of the arm that rotates as the car goes through suspension travel and articulation, allowing the handling to be controlled by the coilovers (from Ride Tech) and rear anti-sway bar without binding. The kit is almost a bolt on, but you do have to weld on the provided axle brackets. The front suspension is all TCI’s IFS, with rack-and-pinion steering and more Ride Tech coilovers. The whole shebang also includes subframe connectors and crossmembers, so it’s almost like putting an entire chassis under an early Mustang.

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The car is owned and built by Wilwood, so you know it has some monstrous brakes. These are their Aero6 Big Brake Front Brake Kit (PN 140-13685-N) with a Quick Silver coating on the six-piston calipers. The rear brakes are the Superlite 4R Big Brake Rear Parking Brake Kit (PN 140-10012-DR), also with the Quick Silver finish.
One of the purposes of The Workhorse Mustang is to get it out and use it at events like the Optima Shootouts, where it wears sponsor stickers and aggressive alignment settings. It’s an evil little horse on the autocross and road course.