1941 Super Spark Plugs

Hi everybody.

Looking for a little spark plug advice. Will be replacing my spark plugs soon, and wonder if anybody uses anything besides the AC 46 per the owners' manual.

Thanks.

Bob Engelhart

'41 Super Coupe

Bob:

I was using AC45 (what Bob's sells) and they were fouling due to my essentially nonexistant compression so I switched to AC47's off EBay. But now that the rings are done am hoping to go back to the 45s.

Cheers, Dave

On the old AC spark plugs, the higher the number, the hotter the plug. The S means there is a "skirt" or area below the threads on the shell.

http://www.clubplug.net/cross.html

Cheers

Grant

Bob:

I was using AC45 (what Bob's sells) and they were fouling due to my essentially nonexistant compression so I switched to AC47's off EBay. But now that the rings are done am hoping to go back to the 45s.

Cheers, Dave

I too was running the AC45 gapped around .025 for past years then i too ran out of usable compression . Now I am in deep into a rebuild .

The hotter plug AC-46 vs/ AC-45 will help with fouling of the sparkplug caused by oil consumption for a while, but the engine will still need a rebuild at some time.