Voith

I am trying to figure out how to set the variocam for turbo application, some of you have done turbo variocam engines, so how did you set it up?

Originally it goes from non-overlap to overlap mode in the 1500-5500RPM frame, reason being that at idle there is no overlap to burn as much as possible, achieve clean emissions and good idle, then from 1500-5500 it is in overlap mode to achieve better filling of cylinders (= more torque) over 5500 it again goes to non overlap for max power.

This is good in NA scenario (or so they say), but what about turbo?

Overlap mode from 1200-3000RPM (or wherever the boost starts building)?

Duke

Easiest is to run a dyno without it and then with it activated and overlay the curves. I did that on my street 968 turbo engine. It was best to just keep it activated til redline.

Raceboy

Best is to test it on the dyno what your particular combo likes most. Can be done with street-tuning (log and analyse engine fuel needs as you adjust the activation point), it is time consuming though.

Why are you asking this? Are you going with 16v turbo setup? Why would you do that??? :O

V2Rocket

so a slovenian is trying to tweak a german system with a spanish diagram..

Voith

If I see correctly on the picture you posted today, now you run with vario disconnected? Always in off mode?

Why not, its all part of 'while youre in there' logic

If it cracks, I can always replace it.


on a us forum

Strangely I found the most information I was searching for on spanish site..

michaelmount123

The cracking is NOT a big issue. It's been blown way out of proportion by RL know-it-alls without practical experience.

Voith

What are your thoughts on variocam in turbo application Michael?

Duke

I don't use it in my race engine. I used it on my 968 turbo street engine with stock cams.

michaelmount123

Others have made these comments, and I agree:

- It should be tested on the dyno since the VarioCam may be advantageous with one configuration, not so on another.

- If stock 968 cams are used, VarioCam will probably work well.

- Performance cams (depending on how radical) probably won't like being moved around that much. The amount of change can be limited, however, with a plate under the top pad on the tensioner which may be good with a rather mild performance cam.