ABB Turbocharging said it will step up its promotion of variable valve train system, Valve Control Management (VCM). VCM helps a turbocharger to manage air actively so that an engine can operate at different speeds, loads and ambient conditions, thereby increasing its range of application and operation. A major market for this technology is gas power plants. VCM offers new options for higher performance engines that need either a wide range of operation or a fast load response, such as on tugboats, off-highway trucks and emergency power generators. Suboptimal air-fuel flow results in greater risk of engine knock, more polluted exhaust and lower efficiency.