[AZ_1LE]

I used to own an Audi RS4, now THAT engine needs a better catch can system (the factory triple-venturi system does not work that well).

The LT4's really don't. The buildup seen on the back of the valves is going to be enough to where you'll want to media blast them around 75k miles whether or not you have a catch can. Not worth the money and headache or the warranty issue.