I need some help from the group, I have a carbed 5.7, I recently did a bunch of maintenance because it was running like trash (carb rebuild, plugs, wires, rotor, sensor in dizzy). It has a thunderbolt V in it. It is running very smooth other than a little hiccup, for lack of a better term. When I performed the timing adjustment I noticed it. At idle it has a little hesitation, you can see it with the timing light. It sporadically jumps timing from about 8 degrees to 10 degrees about every 30 seconds or so. When I set it to 10 it would jump from 10 to 12. I didn't want to over advance it so I backed it off enough that the high side was 10. Other than this the motor sounds great on the muffs and seems to do fine when I advance the throttle, which I can only do so much on the muffs. I have not had a chance to put it in the water yet. Does anyone have any ideas on what this might be or where to start?