3.0L DOHC H-6 cylinder engine.
This engine has an aluminum crankcase, double-overhead camshafts (dohc) chain-driven with four valves per cylinder. The timing chain does NOT have a replacement schedule - suggested replacement of the rubber belt on the 2.5L 4 cyl is 105,000 miles.
The 6 cylinder uses Direct Ignition with an individual ignition coil for each cylinder so there is no distributor or sparkplug wires.
The H6-3.0 produces nearly 30 percent more horsepower and torque than the 165-horsepower 2.5-liter H-4 and is only 0.8 inches longer. Premium fuel, 91 octane, is recommended.Dual-Stage Intake And Exhaust
The H6-3.0 uses a variable intake manifold and a dual-stage muffler to optimize power delivery throughout the
engine speed range. Low-speed and mid-range power have not been compromised for high-rpm power, and vice versa. The
variable intake manifold features an induction control valve that provides two intake characteristics. Below 3,700 rpm the valve remains closed to create a long intake runner length, helping to boost low-end and mid-range power. When the valve opens above 3,700 rpm, the manifold creates a "scavenging" or light supercharging effect, allowing each cylinder to catch
high-pressure waves of intake air bouncing off the opposite side of the manifold.
A mechanical valve in the rear muffler varies muffler volume to help enhance engine power in different speed ranges. At lower
engine speeds (around-town driving, for example), the valve remains closed to provide a smaller-volume muffler chamber. The resulting level of exhaust back-pressure enhances power at these speeds. When exhaust pressure reaches about 22 psi -- which occurs at about 2,400 rpm -- the valve opens to allow exhaust gas through an additional chamber. The resulting
increased muffler volume reduces exhaust back-pressure, enhancing power at higher speeds. Muffler valve operation does
not affect the noise level.