98onyxss

Does anyone know how the phaser is controlled on the VVT motors? Is it pulse width modulated or just variable voltage? Would anyone have some schematics on that? Can you command certain degrees of the phaser with HPtuners? And if you can, would anyone be willing to measure voltages going to it based on different values you command with HPT?

11z71

iTrader: (10)

I believe it's controlled with oil pressure. The vvt engines have a cam phaser sensor on the timing cover that tells the ECM where to adjust cam timing. Also it looks at other inputs and adjusts cam timing accordingly. You can play with cam timing via hp tuners, I have a 2013 gmc sierra with a 6.2. The only thing I did with vvt tables was retard the cam timing 1 degree from 5700 rpm up to the fuel cut off. It definately made a SOTP difference up top in the rpm range.

98onyxss

But what is controlling the oil pressure to advance and retard the cam? There has to be a solenoid somewhere that is either being pulsed or provided a set of voltages. If someone knew what that was, it would be fairly simple to make a module that could control it at either a set point, or make it adjustable for those of us playing with carbs or doing a swap without wanting to tear the motor apart.

cam

iTrader: (9)

Theres a valve in the middle of the cam that is applied by a little electric pin on the timing cover. Entire travel is about 1/4" or so. Yes HPtuners can command different phase values. I havent logged any of this stuff but others on here have if you search it out theres info on it. I dont think it would be very difficult at all to create your own controller for it. Pretty basic actually, I have to give GM credit for keeping it as simple as possible.