The 2016 Mustang is available as a fastback or as convertible, with one of three 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 V6 and 4-cylinder engines both make over 300 horsepower, while the V8 engine makes well over 400 horsepower. 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 five trim levels for the fastback: V6, EcoBoost, EcoBoost Premium, GT and GT Premium. 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.