Plug Gap For Electronic Ignition

[arlen]

I think the stock C-113 calls for a plug gap of .025. I put the electronic ignition in, and a hot coil. What would be a good plug gap to take advantage of the new setup? Maybe .035?

[tnestell]

I opened my gap to 35 thousands with a Pertronix 45,000 volt coil and ignition in 2006. Just recently checked the plugs and all was fine.

[SamsFarm]

I opened my gap to 35 thousands with a Pertronix 45,000 volt coil and ignition in 2006. Just recently checked the plugs and all was fine.

Did you gain any fuel efficiency? Horsepower gain?

[tnestell]

I opened my gap to 35 thousands with a Pertronix 45,000 volt coil and ignition in 2006. Just recently checked the plugs and all was fine.

Did you gain any fuel efficiency? Horsepower gain?

I don't know for sure and this is on a Cub. It did change the exhaust sound from a crackling sound to s smooth sound. It has an inch and a quarter exhaust pipe without a muffler. It starts easy.

The engine, at that time, had recently been rebuilt with 60 over pistons. I believe that it had been through several rebuilds with the block and head decked each time. It has compression readings of over 150 lbs. This engine came out of a power unit on an insulation blower with a broken rod.

[Gary Dotson]

Arlen, the instructions that come with the Pertronix kit says that you (may) open the plug gap to .035". One of mine is set at .035" while the others are still gapped .025", I can't really tell the difference. I probably wouldn't gap larger than .035" but I would open them up a bit. I think .030" is a good compromise.