AOS Failure: what breaks first?

[thstone]

Originally Posted by maytag

2) ... any PCV system that includes such an easy path for the oil to dump into the intake, such as we have with this AOS system, seems like a design-failure. For decades, we've been dumping PCV into catch-cans which then vent to atmosphere, or to header-pipes, and drain back to the sump.

Why don't we simply do that with these motors? What am I missing?

These days, venting crankcase/oil vapors to the atmosphere is a no-no in terms of system design for emissions compliance. Could you implement a catch-can approach? Yes. But it depends on how you feel about defeating pollution controls and how closely Utah monitors emissions compliance.

Originally Posted by maytag

Is there a better design on the market already?

Yes, Porsche has a motorsports AOS that eliminates most of the design flaws of the Boxster production AOS. The part itself is $750 and you'll need some mods to make it work.

Porsche Motorsports AOS

Originally Posted by maytag

What are y'all racers doing?

Because of the high cost of the motorsports component and the cheap cost of the production unit ($75), most Boxster racers run the production component and simply change whenever needed (many racers do it at the track between sessions if they see a cloud of smoke).