Forrester XT cams

[FAER]

i can't find any info on these but i would imagine they are better suited for us turbo guys that the N/A cams..

[xjohnx]

I imagine that most people who are willing to go through the trouble of installing cams will go with a more aggressive cam than the OEM forester setup.

[AdrianG]

What would the "turbo guys" be looking for in cams that the factory cams don't provide? I can see upgrading to stiffer valve springs but the factory cams already have pretty good lift and duration. I wouldn't be surprised if the fa20dit has the same cams.

- AdrianG

[Ross]

That whole lift and duration thing, I would like more of that please. The factory cams work for there intended purpose, and avcs helps, would it be nice to look in to .5" lift or more, yeah. Would it be nice to see something in the 260's to 280's degree of duration based off 0 degrees, yeah. Only time will tell what comes down the line.

[FAER]

Originally Posted by AdrianG

What would the "turbo guys" be looking for in cams that the factory cams don't provide? I can see upgrading to stiffer valve springs but the factory cams already have pretty good lift and duration. I wouldn't be surprised if the fa20dit has the same cams.

- AdrianG

N/a cars do not have the same valve overlap conditions as boosted cars.

[FAER]

There is more thN just lift and duration...

[AdrianG]

Originally Posted by FAER

There is more thN just lift and duration...

That's why I asked, my question is sincere... What do you want in a cam profile for turbo?

I know about lift and duration, if there is more to it please enlighten me.

Aren't valve overlap conditions controlled by AVCS moreso than the cam profile?

[AllDayJonRay]

Overlap is the duration of time that neither intake nor exhaust valves are fully seated. Intake valves beginning opening before exhaust valves are fully closed. This is done in order to move all inert gases from the combustion chamber, so that it may then be filled with fresh, 'unburnt' intake air.

You only want as much overlap as is necessary to remove the inert gases, not so much that new gases pass through the combustion chamber into the exhaust. As FI engines' intake air is under pressure, less valve overlap is required to remove the inert gas.