This q-jet was rebuilt and modified by Cliff 10 plus years ago. It was due for a rebuild as it had some junk in the float bowl. After getting it all back together it has a rich condition when flicking the throttle off idle. I've adjusted the APT, fuel mixture, secondary flap spring ... so all that is good. When I take off the accelerator pump rod, the throttle response is really good.
I think that the power piston spring was a bit too stout so I'm going to put in a lighter spring. Does this sound like the issue and/or jet/rod combo? I don't know what the jets/rods are. I'm only doing around 12hg of vacuum and I tried manifold and ported vacuum to the advance can. I prefer ported which is where I've left it. Any assistance is appreciated.