Thread: Power valve do I need one?

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I'm running a 68 impala 4 door with a 381 sbc pump gas engine has a QF 950 runs a single power valve in the front. Almost everyone tells me to plug it, but I am skeptical because this engine sees different plenum vacuum readings when staged and at WOT going down the track. when foot braking the plenum is at 8 in and at WOT crossing the line at 6800rpm the plenum is pulling 2 to 3 in, take in to account this engine gets shifted at 7200rpm.

So the Main system in a carb basically operates of vacuum a pressure drop in the main venturis(boosters/doglegs) pulls a mixture of air and fuel from the main system in the carb. As engine rpm increase you displace more over a giving time. More air is moved through the intake in a giving time, the flow is faster, the pressure drop gets higher over the venturis and pulls more air and fuel.

THE POWER SYSTEM
I am on the understanding that the power system exists in a carb because at WOT throttle when the plenum vacuum drops this can cause the pressure drop to lower over the venturis and make the the main system inefficient and not deliver enough fuel where as air has more of a tendency to just fall in the carb and cause a leaning effect and power loss. So it basically corrects Air:Fuel ratio at high engine loads

Would it be beneficial to have in my car? I could justify not having one if this was a car that only saw 6000rpm and up all the way down the track, but the engine in my car operates between 3000rpm to 7200rpm the duration of the run