We’ve known that Ford has had a high-performance version of its 2015 Mustang to be called Shelby GT350 in the works for some time now, but the specifics of the car have remained a mystery. What engine will it have? Will it be supercharged or naturally aspirated? Will it have the rumored flat-plane crank? We don’t know enough to confirm anything just yet, but Motor Trend thinks they have a pretty good idea of what to expect from the new high-performance pony car.
According to MT, the Shelby GT350 will feature a motor with a flat-plane crankshaft — a first for an American production car. For those of you not in the know, a flat-plane crankshaft allows for an alternate firing order in the engine and does away with the counter balance weights of a cross-plane crank. The lighter crank allows for the engine to rev higher and more actively. The result: more power.
So why don’t all automaker’s use this design? It has its drawbacks. The majority of flat-plane crank engines are small in displacement, such as Ferrari’s 4.5-liter V8 from the 458 Italia. Without weights to balance the engine, it can produce high levels of shaking and vibration. The larger the engine gets, the harder it is to balance the engine and the worse the vibrations become. Ford is rumored to have a 5.2-liter engine under the hood of its new GT350, making MT’s technical director “highly skeptical” that a flat-plane crank is actually in the car, as the vibrations would be too harsh for a modern vehicle.
MT’s sources say Ford is “still working out the kinks” on the flat-plane crank V8. Apparently, Blue Oval’s engineers solved the issue of vibration from the larger 5.2-liter flat-plane crank engine by attaching a large vibration damper to the end of the crankshaft. This didn’t solve everything though, as the vibrations were still very much noticeable. So much so that they vibrated a bolt out of the car’s starter during testing and shut down the electrical system while the car was at speed. Yikes. Nevertheless, we’re sure they’ll work it out.
As for the engine’s specs, MT says the car should rev happily to a sky-high red line of 7,500 rpm and produce close to 600 horsepower and 430 pound-feet of torque. Numbers aside, this should be one hot ‘Stang when it lands, possible making a debut at the 2014 LA Auto Show.