I have had a Mallory Uni-lite now going on 25 years and am starting to have some missing issues. Car has been running hard all the way to 7200rpm until this weekend. I took it for a little spin and somewhere around 5200 rpms it started to miss. The miss got worse as the RPMs climbed. I am NOT an ignition expert but it did seem as if it was running out of spark. I have the rev limiter off so that was not the issue. (besides, that sounds a whoe lot different) I am also running the Mallory coil that is rated to 8000 rpm. Other than that, no other fancy ignition boxes etc. Where shoud I start checking ?
Typically the Uni-lite optical module is either burned out or not (as least that's how mine reacted). Start by checking for carbon tracking under the distributor cap, coil top, and any potential leakage from the plug wires.
Sounds like excessive plug gap, bad wires or dirty or wet cap. I have also seen coils arc to the primary terminals as voltage requirements go up so check the coil for carbon tracks too.
