Just wanted to share a bit about the reason for a upr dual valve three-port catch can with a clean side separator. The benefits are very good for overall performance and towing etc. When you install a single two-port catch can it only catches oil on the dirty side, and that is just half the battle as you are still allowing the boost to escape and pressurize the crankcase, and now the pistons have pressure on the top, and the bottom of the piston decreasing efficiency and performance. Then if you add a second small two-port catch can, you are just adding a separate cath can that barely catches any oil because you are allowing the boost to escape by not having a check valve on the dirty side catch can to properly redirect the oil to the clean side catch can.
Lastly, here is where the upr dual valve / three-port catch can with a clean side separator becomes a fully functional and highly beneficial part of the equation. When you properly protect the pcv system on a boosted application, you always want a check valve to prevent the boost from leaking into the crankcase and losing power, as you want all the boost to stay in the intake resulting in more torque and horsepower. Now the dual valve / third port comes into play as it still allows the vacuum to suck all the oil into the dirty side of the catch can while the check valve closes and keeps all the boost in the intake manifold resulting in much smoother effortless towing and overall performance.
That is what the three-port is for, as it uses the vacuum from the inlet tube before the turbo to create the vacuum to keep the pcv running smooth and uninterrupted when the check valve is closed during boost. The added products to have a fully functional kit that does not allow boost leaking into the crankcase under throttle or any type of acceleration is very beneficial and will also improve mpg and efficiency as it allows the engine to utilize the fuel and spark curve much better. The added cost is only to cover the required parts to make a fully functional system run properly.
The reason upr recommends dual valve catch cans with a clean side separator is for overall performance and to deliver results that a two-port catch can is incapable of. When everyone says how great a two-port is and look at all it catches, they are missing the big picture as they're not seeing how much that actually does not get caught and escapes through a two-port catch can. Also, never knowing just how much boost escapes through the pcv system back into the crankcase, causing resistance under the piston during the down stroke creating additional resistance and heat. Whereas a upr dual valve three-port will just allow additional horsepower and smoother operation while allowing the pcv system to operate how they perform best.
Hope this helps everyone to understand the benefits much better of a upr dual valve / three-port catch can system with a clean side separator.
Joe