I have an 86 Scarab I with a stock 350. Was wondering what kind of ignition upgrades anyone has done or what would be good for me? When I idle threw a channel at the lake I tend to loose a cylinder and have to run the engine about 2k to get it back. I'm still running the thunderbolt IV ignition. A friend put a hei distributor on his and he lost his tach, whether that was a coincidence or from the upgrade we don't know but I didn't want to risk loosing mine. Anyone have any ideas or what has worked for you? Thanks

The TB IV is very ignition for stock and mild engines. There is no reason you should foul a plug a drop a cylinder with it, unless something is out of adjustment. Carb is probably running too rich at idle.

Yeah thats what we thought at first, but we spent awhile adjusting the idle and timing it and finally put it back to stock. Thats where it runs the best. I think it was 2 or 2.5 turns out on both sides. (Stock carb) It takes about 2 or 3 min. then the problem starts. Any ideas on upgrades?

I still think its running too rich at idle if its fouling plugs. Sommething could easily be wrong with the carb. What plugs are you running???? Try running some AC Rapid Fire's in the same heat range, probably #1's. They have an extended small tip, and won't foul as easy.

The ignition actually came off another boat that was having the same problems and we had it sitting around for a couple of years and when I bought my boat I threw it on there to try it out. He changed his over to hei and it runs better than it ever has. But he also lost his tach when he did this change over. I'm running autolite 25