1974 Thermoquad, 360 HD Truck , Rebuild adding performance modifications

Drilling holes in the primary plates is an old trick to add to the idle circuit when you have a cam that idles at too high an rpm that the idle circuit can feed it. Air bleeds add air to emulsion tube which controls the fuel curve through your rpm range in a Holley, not sure about a TQ.

You have to look hard for a dyno guy thats reasonable, they are out there. In the long run you will be money ahead.