Ads
related to: variable valve timing
Search results
Results From The WOW.Com Content Network
Variable valve timing (VVT) is the process of altering the timing of a valve lift event in an internal combustion engine, and is often used to improve performance, fuel economy or emissions. It is increasingly being used in combination with variable valve lift systems.
The Alfa Romeo Twin Spark engine, introduced in the 1987 Alfa Romeo 75, also uses variable valve timing. [3] [4] The Alfa system varies the phase (not the duration) of the cam timing and operates on the inlet camshaft. [5] Alfa Romeo's variator is a cylindrical chamber that contains a pressure chamber and piston along with helical splines.
The system provides two-stage variable valve lift in addition to continuous variable timing. Continuously commanded by engine control unit, the valve rocker arm switches between high-lift and low-lift profiles on the camshaft, actuated by an oil control valve through a two-feed stationary hydraulic lash adjuster, allowing for either 4.0 or 10.5 ...
Variable camshaft timing (VCT) is an automobile variable valve timing technology developed by Ford. It allows for more optimum engine performance, reduced emissions, and increased fuel efficiency compared to engines with fixed camshafts.
Cutaway view of Variable Valve Timing with intelligence on a ZR engine in Techniquest Glyndŵr. VVT-i, or Variable Valve Timing with intelligence, is an automobile variable valve timing petrol engine technology manufactured by Toyota Group and used by brands Groupe PSA (Peugeot and Citroen), Toyota, Lexus, Scion, Daihatsu, Subaru, Aston Martin, Pontiac and Lotus Cars.
In four-stroke cycle engines and some two-stroke cycle engines, the valve timing is controlled by the camshaft. It can be varied by modifying the camshaft, or it can be varied during engine operation by variable valve timing. It is also affected by the adjustment of the valve mechanism, and particularly by the tappet clearance.
VarioCam is an automobile variable valve timing technology developed by Porsche. VarioCam varies the timing of the intake valves by adjusting the tension on the timing chain connecting the intake and exhaust camshafts. VarioCam was first used on the 1992 3.0 L engine in the Porsche 968.
VVC (Variable Valve Control) is an automobile variable valve timing technology developed by Rover and applied to some high performance variants of the company's K Series 1800cc engine. About [ edit ]