VCT Control

[Michael Woodford MST]

I know how all the mechanicals work but does anyone know in detail anything about the signal that the ecu sends and how vaiable the timing is?

As the 172 doesnt have a cam sensor, am i right that at a certain load site the ecu just fully advances or retards the cam?

What im trying to get at is, Is there only 3 positions? locked, Max advance, Max r****d.

I know the Ford Puma VCT uses a cam sensor and can move the pully to anywhere within max adv & rtd.

Cheers

 

[sideways danny]

only 2 positions. Switches by 16 degrees above a certain load and about 1600rpm

 

[Michael Woodford MST]

It must switch again after 1600rmp?

 

[Fred@BTM]

nope, its a simple system, on at 1600rpm, (stock) it turns off at cira 6500rpm IIRC, i'm no mapping guru though, all i know is from stuff my mappers have done is we leave it turned on past the redline to gain power up top running funny cams

 

[Michael Woodford MST]

Is it purely used to assist idle?

 

[sideways danny]

Primarily yes. Newer versions of the engine in the 197/200 uses fully variable