Ok- I have found some information on this but wanted some opinions. I am finding that with my car running lean 14.7-15.2 at idle the converter will get red hot at times. Has anyone experienced this. I make it richer 13.7-14.2 it looks ok.

With the 14.7-15.2 I was first running .045 gap, cat red most of the time at idle after a ride. I moved the plug gap down to .040 and now it is red only at times.

Now I moved the mixture to 13.7 not red at all.

Is it possible that the 11 to 1 compression is blowing out the spark. I am using the stock HEI coil with the MSD 6AL box.

I also found that this condition only happens after a drive and the hedders and cat are hot. During a startup and warmup of 20-30min no issue. Can the wire resistance increase as they heat also causing a reduction in spark energy. Would anyone recommend that I move up to a larger coil and if so which one.

 

I don't think it's a question of whether you have enough spark or not. I think the problem is you have too much air, ie your running lean. Not enough spark would lead me to believe you have excess fuel and that is not the case. Just enrichen (is that a word) the fuel table a bit and you should be fine.