340 with Thermoquad and MSD distr. with 6A box, recent plugs, good wires.
In my last Thermoquad thread I was diagnosing fuel leaking into the intake. Turned out to be a leaky brass float which I got fixed. This was a #6518s that I had rebuilt not long ago. ('74 440 "Industrial".) Also I had this really dialed in for my 340, great A/F #'s, good plug readings, etc.
Call me crazy, but I looked at my parts carbs and see I also had a #6322 core ('73 Truck 440) in decent shape, so I decided...
340 fuel/ignition issue?
