Key New Features
- Variable Cylinder Management with switching between 6-, 4- and 3-cylinder modes
- Cold air intake
- Magnesium intake manifold (4WD only)
- Active Control Engine Mount (ACM) and Active Noise Control (ANC) on 4WD models
The Pilot's engine is an advanced 3.5-liter, SOHC, 24-valve, 60-degree, V-6, aluminum-block-and-head design that is compact, lightweight and powerful. The i-VTEC valvetrain and high efficiency intake manifold optimize cylinder-filling efficiency across a wide range of engine speeds. Low-restriction intake and exhaust systems, a 10.5:1 compression ratio and roller-type rocker arms further aid efficiency and power delivery across a broad rpm range.
The Pilot has a die-cast lightweight aluminum alloy block with cast-in-place iron cylinder liners. Made with a centrifugal spin casting process, the thin-wall liners are high in strength and low in porosity. The block incorporates a deep-skirt design with four bolts per bearing cap for rigid crankshaft support and minimized noise and vibration. Both the block and caps are heat treated for greater strength.
Crankshaft, Connecting Rods and Pistons
A forged steel crankshaft is used for maximum strength, rigidity and durability with minimum weight. Instead of heavier nuts and bolts, connecting rod caps are secured in place with smaller, high-tensile-strength fasteners that screw directly into the connecting rod. Short-skirt, cast-aluminum, flat-top pistons are notched for valve clearance and fitted with full-floating piston pins.
Like other Honda V-6 powerplants, the Pilot V-6 cylinder heads are a SOHC design, with the cams driven by the crankshaft via an automatically tensioned toothed belt. Made of low-pressure cast, low-porosity aluminum, each cylinder head incorporates an integrated exhaust manifold to reduce parts count, improve flow and optimize the location of the close-coupled catalyst on each cylinder bank.
The cylinder head employs four-valve combustion chambers, the best approach to optimum performance with excellent fuel efficiency and very low emissions. Valves are clustered near the center of the bore to minimize combustion chamber volume and to provide ample squish area. A 10.5:1 compression ratio helps maximize thermal efficiency, power output and fuel efficiency. One centrally located camshaft per cylinder bank is driven by a fiberglass-reinforced toothed belt. Head gaskets are made of high-strength materials to contain combustion pressures.
Dual-Stage Intake Manifold
The Pilot uses a dual-stage intake manifold that is designed to deliver excellent airflow to the cylinders across the full range of engine operating speeds. On four-wheel-drive models, the two-piece manifold is extremely light due to its cast magnesium design. The intake manifold on two-wheel-drive Pilot models is constructed of aluminum using an identical design.
The induction system significantly boosts torque across the engine's full operating range. Internal passages and two butterfly valves within the intake manifold are operated by the powertrain control module to provide two distinct modes of operation by changing plenum volume and intake airflow routing.
At lower rpm these valves are closed to reduce the volume of the plenum and effectively increase the length of inlet passages for maximum resonance effect and to amplify pressure waves within each half of the intake manifold at lower rpm ranges. The amplified pressure waves significantly increase cylinder filling and torque production throughout the lower part of the engine's rpm band.
As the benefits of the resonance effect lessen with rising engine speed, the butterfly valves open at 4200 rpm to interconnect the two halves of the plenum, increasing its overall volume. An electric motor, commanded by the powertrain control module, controls the butterfly valves. The inertia of the mass of air rushing down each intake passage helps draw in more charge than each cylinder would normally ingest. The inertia effect greatly enhances cylinder filling and the torque produced by the engine at higher rpm.