I’m having a helluva time trying to get rid of a stumble in my tune up. It happens at very light throttle while cruising when I try to roll into it just a little. It’s like a little hiccup then it smooths right out. Setup: 318, comp xe268, action plus, headers. Carb is OLD Holley 4777 650DP. 71/82 jets 31/31 shooters Blue pump cams in #2 position Floats are at the bottom of the sight hole Timing is 22/34 Vacuum pod is plumbed to spark port. IAB at 1.5 out 10.5 PV 10” hg @ idle , around 20” at cruise. Transfer slots are .045” exposed Idles at 800 Where should I start? It runs good everywhere else and I don’t want to totally destroy the tune while chasing this damn stumble. I unhooked the vacuum pod and plugged it and the stumble was totally gone, but I would like to keep the vacuum advance. Should I start by drilling out the IFRs?