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Have a 300 engine from parts truck. Truck is a 66. Engine is a 75 Fred Jones long block. Engine had dead miss #2 cylinder. Rocker studs had pushed up so valves were not opening. Replaced rocker studs with treaded type. Rebuilt carb (Carter YF). Engine runs much better but still has a miss. Replaced lifters (Clevite) and adjusted valves. Issues are that 7 rockers are oiling properly (steady stream at idle) 5 rockers are oiling but not a steady stream. Engine still has intermittent miss. Dwell is 37 degrees, idle is 500 rpm, timing is 8 degrees btdc. PO installed new plug wires but they are graphite. Am I correct that you are not supposed to use graphite wires with a point based ignition system? Engine holds 30 lps of oil pressure after warm up. Compression is 150-155 across all cylinders. Miss is worse after it warms up. Should I check the coil?
Thank you for all your help!
Can you isolate the miss to one or two cylinders? Or does it miss on all cylinders on a random basis?
Random miss, maybe test or replace the coil.
Vacuum leaks? Esp intake gasket area.
Plugs?
Wires arcing, cracked? Graphite with points isn't an issue.
Get rid of the points when you can. Several options available, you can search them out. At the same time, if you don't have a high voltage coil, you should switch over to those too, as the high voltage, as well as getting rid of points, is a proven winner for reliability and more consistent running.