Hello!
I've used the search and haven't found what I was looking for. Can someone explain to me how the variocam plus works?

Does it control the intake side, exhaust side, both sides?
Is it continuously variable or is there a cross over point?
Is it based on RPM, vacuum, or throttle position, some combination of these?

Please try to explain it to me like I'm not a mechanic or engineer.

Thanks!

Oh yea, my car is an '02 C2
Andy

 

I'm also curious. would be nice to have some definitive answers!

 

Nobody knows? Andy

 

You have to understand Variocam first and work your way up. I'm not a mechanic so here is my try. There is two drive chain on the engine (front/back) each have a tensioner on it. If you move the tension in/out you can retard the timing of the intake/exhaust valves. By playing with these tensioners you can adjust the timing of the the cams on the intake/exhaust valves to make the engine PUUURRR resultin wider torque band, fuel usage and emmisions.
Variocam plus is similar to hondas vtec so if you know vtec you know variocam plus... I think the plus changes the length of the tappets by having a locking mechanism to make them use of a different set of cams that is more of an aggressive... In short Variocam Plus is a sweet setup. This egine is 34 years of evolution.

 

I'm very familiar with VTEC and VVT-i on the Honda and Toyota. VTEC comes in two variaties, intake only and intake and exhaust. The points that they ingage are computer controled to a set RPM. There are cams with 2 sets of lobes, high end and low end,(adjusting valve duration and overlap.) and a solinoid actuates which profile is being followed. VVT-i uses both intake and exhaust and is continuously variable accross the RPM band, adjusting valve duration and overlap. So my question is, what does the Porsche system manage? Timing, duration, overlap, intake, exhaust, both, continuously or at set points? Is anyone familiar with these details? Thanks again. AA

 

To answer my own question, I found this. Thanks Rennlist. http://wheeltalk.fancal.net/wp-conte...0explained.pdf

 

from what i understand the vtec is more sophisticated than Porsche, but dont know enough details.

 

I don't know if that is true. VarioCam gives the P-car the benefits over a much wider RPM range, e.g. ultimately the engine provides a much more gradual application of power over the full RPM range, as well as more torque.

VTEC is more of an on-off switch. It's on after 5K and off before... more beneficial if you're on the track, otherwise it's like driving a Civic.

 

All I know about Variocam is that it kicks in at 3200 RPM and you feel a slight "hiccup" in your rpms as you're accelerating.
Now that I pointed it out, I'm sure you'll look for it and feel it

 

I definately feel mine at 3200 RPM especially in 1st gear, it is accompanied by a strange metalic sound.