juliem

Folks, I don't know nothing fer sure BUT

The valve is L shaped with the piston basically at the elbow of the L (excuse the poetic license). The piston blocks the path of air flowing from one side of the L to other. When the piston retracts, the flow isn't blocked. When installed in one direction, the boost (flow) hits the piston head on. Flip the valve, and the boost hits the side of the piston.

This discription is based on looking into the ends of the valve. That's why they say flip it and get rid of the noise.

I make all these claims only because I looked at my valve and pushed on the piston and all that and that's how it seems to work. But I'm no Audi tech

TTinHongKong

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juliem

Bailey was certainly the more sturdy feeling of the 2 valves.

BrunoTT

This is exactly what Todd told me and it worked.