hi matt, maybe you can help me out. I'm running mech. hilborn fi on my nostalgia 1952 mgtd. the fi is on an 327 eng. that was just built for this season. when we went to start it the # 7 cyl. is back firing through the #7 injector tube. we checked for bad wires, cracked mag. cap, checked valve springs and rocker arms for anything broken or loose also re adjusted the valves.still popping through the #7 inj. tube. this happens mostly at idle. we even checked for vac. leaks.any ideas before we pull manifold and head off. we also did a leak down test and that didn't show us any problems. we can only try going though all that we checked again. but were hoping for some fresh ideas. Thanks Mike