Shortly after taking delivery of their 2015 Mustang GT Coupe, Hillbank Motorsports entered it into Global Time Attack’s Super lap Battle at Buttonwillow raceway on November 14th. Mike Doscher from Hllbank Motorsports who piloted the Mustang during the competition explains their strategy for the day was essentially one of information gathering,“Our objective was to set a baseline and get an impression of all the changes that are going to be made.”
Hillbank ordered their 2015 Mustang with the GT Premium package highlighted by the potent 5.0L Ti-VCT V8 . It also adds a 3.31 limited slip rear diff, engine oil cooler, selectable-effort Electric Power-Assist Steering (EPAS) and vented disc brakes (14-inch rotors, 4-piston calipers in the front and 13-inch rotors with single-piston calipers in the rear), Launch Control, 18-inch wheels and P235/50R18 Pirelli P Zero Nero all-season rubber, Selectable Drive Modes and includes Track Apps, which provides real-time data on the pony car’s performance on a 4.2-inch LCD screen.
The only modification made to the otherwise stock pony has been the installation of a Magnaflow competition cat-back system, which has been touted as adding as much as 30 hp. How is that remotely possible from a simple catback system, you ask? The stock resonator and mufflers of the S550 have been developed to adhere to strict overseas market restrictions, so removing them in favor of a more free-flowing unit will reduce weight while adding power. It also sounds pretty badass.
Doscher acknowledged a the lack of rebound dampening and lamented that the stock shocks didn’t hold up well to the car being thrown from corner to corner. “This car is world’s better than the outgoing model,” says Doscher, “There are flaws with the car on the track however which we plan on addressing.” The fastest base lap time was a 2:07, with Doscher behind the wheel, which allowed them to squeak into the top ten in the finals. Doscher admits that the performance was respectable for a 3,800 lb-plus stock car but is convinced that the addition of track tires and the KW V3 Clubsport suspension alone will be enough to drop that time below two minutes. He did admit that the 14-inch Brembo brakes were free of fade and well matched to the P Zeros but there is plenty of other work to do.
Hillbank’s model didn’t feature the Recaro seat option, which will be among the first changes made. “The stock seats are going to leave you burring your knee and bending the steering wheel to stay in control, says Doscher, “We’ll be removing most of the interior, including the stock seats in favor of a set of racing buckets from Cipher.”
The ultimate goal for Hillbank Motorsports with this Mustang is to build a full road race vehicle that is still as street legal as they can keep it. This will include a full roll cage, six-piston brakes and TSW wheels. Additional plans for the car include more aggressive brake pads, steel braided lines and upgraded fluid. While Doscher admits that the Pirelli P Zero Nero tires are fantastic in their segment, they howl when pushed and don’t provide as much grip as he would like. They will therefore be moving to a 285-series Hankook RS3 that will be better suited to the class they will be competing in and help with corner entry and sustained cornering.
Keep updated on the project by visiting the Hillbank Motorsports website.