Holley Power Valve Styles & Gaskets - Holley 715

[JWH]

I am hoping for some education on Holley Power Valves and Gaskets in general. And what is recommended on a Holley 715 carburetor on a GT350.
    Pictured are three styles of Holley power valves. One has two rectangular windows, one has four rectangular windows and one has four round holes. What are the advantages to each? Which should be used on the Holley 715 carb?
      The second picture shows two styles of Power Valve Gaskets. One is a simple, round gasket and the other is a round gasket with three tabs. Which gasket works with the above power valves? Are they interchangeable? Are there different thicknesses of PV gaskets?
Thanks in advance.
Jeff
       

[Drew Pojedinec]

Small holes take smaller gasket.

Honestly?  You can use any successfully.

[98SVT - was 06GT]

The secret to power valves is the number stamped on each. Yours should be an 85 which means it opens when the vacuum drops to 8.5".