Tuning with jets, Power valves and an O2 guage

Frankenduster said
I've been busy with other stuff, but I'm still curious if I can get this thing tuned right.
I have been looking at some other threads elsewhere on tuning. I read where it was suggested to run smaller jets for leaner cruise A/F numbers but then enlarging the Power Valve Channel Restriction. Sounds good to me. I haven't tried it yet but I'm tempted to buy another metering block to modify, OR....
I have several Holley metering blocks to practice with. I'd prefer to screw up with a throwaway piece.
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This is the correct way to tune the carb. The main jets are for your cruise setting, not WOT as many think.. The power valve is your WOT or under load setting. The power valve orifice is the one you enlarge or reduce to get the correct values at WOT.
Just make sure that your carb is not too small as it will become a restriction at WOT , build vacuum again in the intake and close the power valve, if it is at a very low value. You will then get a leaning out situation at high RPM... not good..