A vane-type camshaft phaser having a rotational authority between 40 crank
degrees before TDC and 30 crank degrees after TDC. The phaser includes a
stator seat formed at a rotation position intermediate between full
advance and full retard. A locking pin in a vane of the rotor engages the
seat, locking the rotor at the intermediate position. The pin is
disengaged by pressurized engine oil independent of oil flows for advance
and retard of the rotor. The oil is controlled by a dedicated valve.
Preferably, the seat and the ends of the locking pin are vented by
passages in the rotor and stator which are aligned when the rotor is at
the selected locking angle to remove oil resistance to entry of the pin
into the seat. To position the locking pin over the seat, phasing rate is
reduced to allow time for the locking pin to engage the seat.