Maxxecu VVT tuning - cam target understanding

Hi everyone,

I'm currently tuning my Focus ST with a fully built volvo T5 engine equipped with newman stage 2 aftermarket camshafts. I'm wondering the best setup for the VVT control system and my first question is about the meaning of values we can found in MAXXECU Mtune software. It is not clear whether they are talking about degrees before TDC, or just about relative advance values compared to the camshaft rest position. VVT settings are also configued on "inverted" for the position targets meaning increasing the value add more retard according to the help but this looks weird as the base values are higher in low RPM than in high RPM (meaning there are adding retard where we should advance the intake cam to increase torque??): https://www.maxxecu.com/webhelp/settings-vvt-cam_position_inputs.html

I've attached some picture of the tables as provided in the base map file for this engine. For both intake and exhaust, we can see that values are higher for low RPM and high load. That would be logical for exhaust (if the values are really inverted as stated by the documentation) but looks more weird for intake.

Thank you in advance for your support.

P.S: thank you for the amazing community and course quality. This is really cool.

The timings refer to "0.0", so they must be relative to the original position - kinda obvious.

Industry standards have camshaft timing(s) in crankshaft degrees.

You put your finger on something that can be confusing, as some manufacturers will have the default value/timing of the camshaft in the advanced position, and others the retarded position, so it's important to know if one is advancing or retarding. That's why that third image highlights this option - the "0.0" will always be the start point, so one will be adding or subracting form that value.

For VVT engines I've worked with, the Intake cams would be advanced from their normal, maximum retarded position. So I would use Normal. Exhaust cams are the opposite, they are retarded from their default position (maximum advance), I would use Inverted for that. With that, the exhaust table would retard the cam, and the intake table would advance the cam. The tables looks about like I would expect, but am surprised there is no Intake cam advance below atmospheric pressure,

Thank you guys.

Yes I am also surprised by the default settings saying that intake cam sensor direction is also inverted meaning we are adding retard in low RPM to the intake cam. And like you said it's also weird to have no advance below 80 kPa.

Someone from the maxxecu forum gave me extra informations so I put them here if this can help:

The Volvo VVT is in its maximum retarded position when not energized and when energized the cams advance.

Intake can go up to 50 degrees advanced, exhaust I believe 30.

So target values are definitely advance values from the max retarted position which makes it quite convenient and understandable for the maper.