Track Drive: Ford Shelby GT 350 & GT 350R by Larry Nutson +VIDEO
By Larry Nutson
Senior Editor and Bureau Chief
The Auto Channel
Every day is full of decisions. Some are big and some not. In the life of an automotive journalist some decisions involve conflicting or overlapping invites to new vehicle introduction and information events.
The choice was easy. It would be track time for me.
My invite was from the Ford Performance Team to join a number of other auto writers and drive on the fabled 4.2 mile Road America race track in Elkhart Lake, Wisconsin. We would have time behind the wheel of not only the Shelby GT350 but also the said-to-be-awesome GT350R. This was to be special.
Ford Performance is conducting an exclusive 2015 GT350 North American Track tour at four historic road courses in the U.S. in 2015 – Mazda Raceway Laguna Seca, Road America, Lime Rock Park and Sebring Raceway. We drove laps with a pro-driver in the passenger seat and were immersed in a complete technical overview of the GT350 and GT350R presented in the Ford Performance Garage.
Ford’s new Mustang that was introduced last year features new, fully independent front and rear suspension mated with a stronger and lighter platform and body structure with torsional stiffness increased 28 percent over the previous model. It provides the basis for creating these two world-class sports cars--the GT350 and GT350R.
Before I get in to many of the technical details, take note that these two Shelbys don’t come cheap. The GT350 has a base MSRP of $47,795 and the GT350R is priced starting at $61,295.
Powering both is a new 526HP, all-aluminum 5.2-liter V8 engine. It’s the first-ever production V8 from Ford with a flat-plane crankshaft. This engine architecture is typically found only in racing applications or exotic European sports cars. Unlike a traditional V8, where the connecting rods are attached to the crankshaft at 90-degree intervals, this design evenly spaces all crank pins at 180-degrees intervals.
The 180-degree, flat-plane layout permits a cylinder firing order that alternates between cylinder banks, reducing the overlap of exhaust pressure pulses. When combined with cylinder-head and valvetrain advancements, this permits better cylinder breathing, further extending the performance envelope of the V8.
The result is the most powerful naturally aspirated production Ford engine ever, at 526 horsepower, with a torque peak of 429 lb.-ft. The engine has a very broad torque curve and is very high revving with an 8,250 rpm redline. I hit the rev-limiter a couple times on my track drive. The throaty engine whine and exhaust note is something to behold in person. I noticed plenty of engine response and flexibility within each gear of the lightweight Tremec 3160 six-speed manual transmission. Around Road America most of the turns could be taken in third gear with plenty of torque for strong track-out driving. A standard Ford-tuned 3.73:1 Torsen limited-slip differential optimizes cornering grip and straight-line traction.
Front chassis stiffness is further improved on GT350 with an injection-molded carbon fiber composite grille opening and optional lightweight tower-to-tower brace. The front track has been increased while spring rates and bushings have been recalibrated all around, with lower ride height compared to the everyday Mustang GT.
GT350 makes use of extra-stiff 19-inch aluminum alloy wheels – 10.5 inches wide in front, 11.0 inches in the rear. Fitted with Michelin Pilot Super Sport Z-rated tires, 295/35 on front and 305/35 on the rear, with GT350-specific sidewall construction, tread face and compound.
Ultra-quick responsiveness to changing road or track conditions is provided by the first-ever Ford application of continuously controlled semi-active MagneRide dampers. Fitted in the optional Track Package on the GT350, the dampers are filled with a hydraulic fluid impregnated with iron particles; when an electric current is passed through the fluid, a near instant adjustment of the suspension performance can be made.
The bodywork from the A-pillar forward is all aluminum and unique to this high-performance model, and up to two inches lower than Mustang GT. The new aluminum hood has been lowered and sloped, compared to the base Mustang. It’s tightly wrapped around the engine for the smallest possible aerodynamic signature. Front and rear aero elements have been balanced to work together on the track. The fascia has been resculpted to provide the aggressive lower front splitter with maximum pressure and a ducted belly pan delivers significant downforce. The hood outlet acts as a heat extractor while also reducing underhood lift at high speed. At the rear, much of the engineering was focused on creating an aggressive functional diffuser doing double duty to increase downforce and provide cooling air to the optional differential cooler, and a subtle lip spoiler across the trailing edge of the decklid increases downforce without adding excess drag.
On the inside there’s specially designed Recaro sport seats with a unique cloth. A flat-bottom steering wheel makes it easier for the driver to get in and out and more ergonomic on the racetrack. Gauges are upgraded. Chrome and bright finishes have been reduced or eliminated to prevent any sun glare that may distract the driver. There’s also a head-up shift light so you can keep your eyes where you are going and still know when to shift.
An all-new integrated driver control system allows selection of five unique modes that tailor ABS, stability control, traction control, steering effort, throttle mapping, MagneRide tuning and exhaust settings depending on driver preference to achieve maximum performance.
As for the GT350R, the engine and transmission are the same. However, a combination of changes to aerodynamics and suspension tuning to the new Shelby GT350R Mustang lead to the most race-ready, road-legal Mustang ever.
Stiffer front springs and MagneRide dampers are fitted on the GT350R.
Significant engineering innovations result in weight savings and aero improvements to benefit on-track performance. Ford is the first major automaker to introduce carbon fiber wheels that have been offered on only a handful of exotic supercars as standard equipment on Shelby GT350R Mustang.
Shaving critical unsprung weight, the 19x11-inch front and 19x11.5-inch rear wheels weigh approximately 18 pounds each and provide 16 pounds of unsprung weight reduction per wheel compared to the equivalent aluminum wheel. The wheels also provide a reduction in rotational inertia of more than 40 percent, which positively impacts acceleration and braking performance.
Ceramic plasma arc spray on the front wheels – the same process used on the original Space Shuttle main engine turbine blades – provides thermal protection from brake heat.
The lightweight wheels are fitted with Michelin’s top-shelf Pilot Sport Cup 2 high-performance tires, 305/30 up front and 315/30 in the rear, with rubber compound and a construction unique to the Shelby GT350R. This combination of incredibly stiff and light wheels with bespoke tires offers exceptional steering feel and levels of performance.
The GT350R was put on a diet. Items removed include air conditioning, the stereo system, rear seats, trunk floorboard and carpet, backup camera and emergency tire sealer and inflator. Exhaust resonators also have been removed for weight savings with the benefit of creating a sharper exhaust tone.
Shelby GT350R is more than 120 pounds lighter than the Shelby GT350 Track Pack model.
Revisions to the front splitter maximize downforce, while an all-new high-efficiency carbon fiber rear wing has been added for track competition. The wing moves the vehicle’s center of pressure rearward while improving downforce and lift balance – ideal for high-speed track work like we experienced at Road America’s long Kettle Bottoms back straight.
Exterior touches include red painted brake calipers, red pin striping at the edges of the optional over-the-top racing stripes and Shelby GT350R badging. Inside is high-contrast red stitching, Shelby GT350R badging and the D-shaped steering wheel fitted with a red center mark at the top.
Ford offers an optional Technology Package on the GT350 and an Electronics Package on the GT350R in case you want to add back in some creature comforts. How about a track drive with air conditioning?
Now that your adrenaline is pumping, go to www.ford.com to get more info on this street-legal race car. By the way both the GT350 and the GT350R are a lot of car for the street. Think about a membership in one of the now-popular private race-track based car country clubs with your own on-site garage-aminium.
© 2015 Larry Nutson, the Chicago Car Guy