Stop in for a cup of coffee

I can tune a AFB real well. My 426 wedge got over 20 MPG with a AFB on it. But Holley is a different story...
Oh hell Tim, you should be fine.
Instead of Step up spring and rods, there's a power valve (with a spring in it) and power valve restriction channels.

The other difference is the Holley idle circuit only has one fuel restrictor and one air bleed. I think that makes them more sensitive to getting the throttle position in the correct range at idle.