MIVEC

MIVEC, as with other similar systems, varies the timing of the intake and exhaust camshafts which increases the power and torque output over a broad engine speed range while also being able to help spool a turbocharger more quickly and accurately.

[5] Similar improvements were seen when the technology was applied to the 1994 Mitsubishi FTO, whose top-spec GPX variant had a 6A12 1997 cc DOHC 24 valve V6 with peak power of 200 PS (147 kW; 197 hp) at 7500 rpm.

The basic operation of the MIVEC system is altering the cam profiles and thus tailoring engine performance in response to driver input.

[8] In essence, MIVEC serves the same function as "swapping cams", something that car racers might do when modifying older-design engines to produce more power.

The intake rocker arms contain internal pistons, which are retained by springs in a lowered position while the engine speed is below the MIVEC switchover point, to avoid contacting the high-lift T-shaped levers.

The resulting reduced pumping loss of the larger valve overlap yields higher power output and a reduction in friction.

Under a light throttle load, the intake and exhaust valves in two of the cylinders would remain closed, and the reduced pumping losses gave a claimed 10–20 percent improvement in fuel economy.