The desmodromic valve engine, widely used by Ducati, uses cams and levers to close its valves in place of what conventional mechanism?
Desmodromic valve A desmodromic valve is a reciprocating engine valve that is positively closed by a cam and leverage system, rather than by a more conventional spring.
Volvo SI6 engine Volvo designed the SI6 ("short inline 6") straight-6 automobile engine for use in 2007 models. An evolution of the company's long-used straight-5 Volvo Modular engine, which itself is an evolution of the Volvo B6304 straight six engine, the SI6 can be mounted transversely for front wheel drive or all wheel drive applications. Despite the added cylinder and displacement, the engine remains compact, and is in fact 1 mm shorter than the previous straight-5. The engine was initially offered in two displacements — a 3.0 L turbocharged version and a 3.2 L naturally aspirated version. Both offered variable cam timing, though only the turbo version varies both the intake and exhaust valves. On top of the variable cam timing used on the intake cam of the naturally aspirated engine it also had variable valve lift by using Cam Profile Switching (CPS).