Porsche redesigned its least-expensive car for 2005, giving it more power, a new interior, and revised styling. Size and weight changed only fractionally from the 1997-2004 version, and Boxster remained a 2-seat convertible with a mid-mounted, horizontally opposed 6-cyl engine. It returned in base and S models, both with a power soft top and heated glass rear window. The base retained a 2.7-liter engine, but with 240 hp vs. 228. The S reprised a 3.2-liter, but with 280 hp vs. 258. A 5-speed manual transmission was standard on the base model. A 6-speed manual was standard on the S, optional on the base. A 5-speed automatic with manual-shift capability via steering-wheel buttons was optional on both. ABS was standard, as was the previously optional traction/antiskid control. Base models traded standard 16-inch wheels for 17s and are available with the 18s standard on the S; 19s were optional on both. Front torso side airbags were included, as were side airbags that deployed from the doors. Options included leather upholstery and a navigation system. An available Sport Chrono Package included a dashboard stopwatch and controls that modified throttle, traction, and suspension systems to suit racetrack-type driving. Also optional was Porsche's Active Suspension Management with normal and sport settings. The S was available with ceramic composite brakes.