it's not 'on-off' - it's variable cam phase +/- 20degrees (or it might be 20deg retard only) controlled by a PWM output from the ecu. This opens/closes the solenoid by variable amounts, adjusting oil flow/pressure into the cam pulley and pushing out/letting in a sprung helix arrangment which causes a rotation of the shaft relative to the pulley.

I *think* from memory that with no PWM output / solenoid shut, the shaft defaults to fully retarded.

Valve springs are '10% uprated' according to ETIS, but from what rate I don't know.

Block is the same as 2.0L black top, head has smaller combustion chambers to give 10.5:1 compression iirc.

Rods are sinter-forged like in the zetec-se.