How to modify your Holley Power Valve Circuit

[zrayr]

Originally Posted by Tom Kirkham

Every carb is different. You will need a wide band O2 sensor to get to the right size hole. It is safer to start with bigger. A quick way to see if this is what you need to do is insert a piece of wire in the PVCR to make the effective hole smaller.

In the stock Holley metering block I am not aware of any inserts in the PVCR. Of course in the idle circuit their typically is a brass insert.

Tom,

can you envision just using the air bleed jets instead of a brass set screw ? Is there enough material in the metering block to set the bleed jets in deep enough to clear the power valve ?

Z. Ray