Variable valve lift on Audi versions of the EA888
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EA888 motor - cylinder head & valvetrain
cast aluminium alloy; four valves per cylinder, 16 valves total, low-friction roller finger cam followers with automatic hydraulic valve clearance compensation, toothed chain-driven double overhead camshaft (DOHC), continuous vane-adjustable variable intake valve timing, Audi variants have two-stage "valvelift" inlet valve lift variable control
See this review for more info on the EA888 motor used in the Audi. Apparently: Volkswagen's EA888 version in the Mark 6 GTI does not use the valve lift tech control. This feature is only reserved for Audi at this point in time. Goes part way to explaining why Audi's cost more. Similar thing with Skoda not having EDL/XDS electronic diff.
Driven: 2009 Audi A5 2.0T FrontTrak Ethanol Test Mule
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Planned for the higher-cost applications of the 2.0T-FSI like Audi's A4 and A5, an even more efficient and powerful 2.0T-FSI will come equipped the company’s unique new valve control system known as valvelift. This component alone is good for five percent better fuel economy, but it also further augments torque, making turbocharged applications like our A5 2.0T mule feel like a brawny naturally aspirated V6.
Unlike other bulky and complex systems, valvelift is cleverly simple, with control directly on the camshafts that allows for lightning quick adjustment – just two turns of the crankshaft. Employment of valvelift provides the ability of the engine to dethrottle intake under partial load. By varying patterns of the two inlet valves, the charge is specifically tuned for optimized consumption and power. Where this seriously translates into fuel savings is pulling at constant speeds under partial loads – basically highway and even high-speed autobahn cruising.
Currently, Audi claims the system is stable at engine speeds reaching 7,200 rpm, suggesting a wide compatibility for valvelift applications in Volkswagen Group offerings will eventually be seen. However, valvelift is not yet compatible with high-revving mills like the 4.2-liter V8 found in the RS 4 and R8.
Cheers
WJ