By placing a cam phasing system on the camshaft , a pushrod engine can be tuned to take much higher levels of exhaust gas recirculation.
But unlike a living brain that controls heart rate and respiration, a conventional camshaft can't alter the valve events.
Since the advent of common rail fuel injection, the mechanical camshaft no longer plays a role in fuel management.
Rather than open and close its valves with conventional camshaft , pushrods or cam chain, lifters, rocker arms and valve springs, the camless engine employs an electro-hydraulic actuator mounted above the valves.
The combination of a center-mounted spool valve and check valve allow the camshaft 's torsional energy to assist actuation, rather than oppose it.
A timing belt or timing chain links the crankshaft to the camshaft so that the valves are in sync with the pistons.
During conventional combustion engine operation, the camshaft causes the intake and exhaust valves to open and close in a synchronized fashion to let in air and fuel and to let out exhaust.
Like the previous engine, it uses twin overhead camshafts with four valves per cylinder, along with variable timing on the inlet valves, which combines with the variable inlet manifold to maximize torque spread.
The newer model has just four cylinders but has been beefed up in other areas with twin overhead camshafts , four valves per cylinder, turbocharger, intercooler and an electronically controlled, high pressure, fuel injection system.
The engine is a 1.8 litre petrol with twin overhead camshafts and 16 valves.