The 2017 Mustang is available as a fastback or as convertible, with one of four engines. The base engine is a 3.7L V6, while the mid-level engine is a 2.3L turbocharged 4-cylinder. More powerful Mustang GT variants are powered by a 5.0L V8. The top of the line engine is a 5.2L V8 powering GT350 models. The V6 and 4-cylinder engines both make over 300 horsepower, while the V8 engine in the GT makes well over 400 horsepower. The GT350 is rated at 526 hp. In other words, the Mustang is fast in all of its forms. All engines can be mated to either a 6-speed automatic or a 6-speed manual transmission. Adjustable driving modes such as Normal, Snow/Wet, Sport and Track allow drivers to custom-tune the responsiveness of the Mustang to the task at hand. There are seven trim levels for the fastback: V6, EcoBoost, EcoBoost Premium, GT, GT Premium, GT350 and GT350R. The convertibles simplify things by only offering V6, EcoBoost Premium and GT Premium trims. V6 Mustangs offer 17-inch wheels, HID headlamps, power mirrors, a leather-wrapped steering wheel, power windows and door locks, a 6-speaker stereo with Ford's SYNC system and a rearview camera. EcoBoost models come equipped with Ford's 2.3L 4-cylinder, which is more fuel efficient than the V6 while still making comparable power. EcoBoost models' standard equipment includes 18-inch wheels, a 6-way power adjustable driver's seat and power adjustable passenger seat, and an intelligent key. The EcoBoost Premium trim adds dual-zone climate control, heated mirrors, additional exterior lighting and a 9-speaker stereo with SiriusXM satellite radio compatibility. A Pony Package is offered on this trim. The Mustang GT and GT Premium come similarly equipped to the EcoBoost trims, though of course GT models are powered by fire-breathing V8 engines rather than fuel sipping 4-cylinder turbos. Several performance options and packages are available, including a range of rear axle ratios, several wheel choices, and Recaro sport seats. A California Special Package adds 19-inch ebony wheels, ebony suede seat inserts with red stitching, special door panel inserts, an aluminum dashboard finish and more. The Shelby GT350 and GT350R variants use a special flat plane crankshaft that allows its big V8 engine to rev to over 8000RPM. It's a very special engine, using technology that's normally found in high end supercars. Usually, a larger V8 means lots of torque lower in the rev range, but a compromised ability to make power at higher RPM. With the Shelby GT350 there are no such compromises. The GT350 also gets magnetic shocks, a more aggressive exterior package and various interior badges.