This is for a 440 six pack 4 speed car. I have 15" of vacuum on my gauge. I currently am using a 6.5 power valve. What is the rule of thumb to determine what size power valve is needed.

[img]http://www.imgur.com/hxlGUJt.gif[/img]
4-speed
3:54 Dana
13.01 @107.93 with street tires (not hooking up)