Big Spark Plugs gas vs. LP 403

[Mopower]

I have a 403 at about 7:1 compression or a little higher (old LP gas power unit with GE30E H-C heads). The heads use the big old plugs. I just stuck some junk plugs in it to keep water out. What's plug number do I use? I won't use champions, but I can convert from a champ number. I think I used W13 in a U gas.
 

[Captainhookerus]

Try some of these.
http://www.sparkplugadapters.com/
 

[Mopower]

I probably will eventually. A buddy put my sawmill LP 403 in Dad's GB gas and needs plugs to fire it up. The 40 yr old plugs don't work too well. Two of them fire...sorta lol.
 

[pplowboy]

Hey mopower ,, i look at my gtb..i got e heads on my gtb , has big plugs ,i have champions i think in it...its a cross to motel t ford , is same plug i believe, but i can look for no. On my plugs if ya like
 

[Mopower]

Just picked up some W10 champs. It was the only brand they had 4 of. $30! Not sure if the heat range is too cool.
 

[Charlie Bilerx]

Mopower,
Try Autolite #3076 in those 7/8"-14tpi holes. Long ago I decided to stop using those Chumpion fishing sinkers for plugs.

Happy motoring.
Charlie
 

[Charlie Bilerx]

Charlie Biler,
Next time; proofread something before the big fat finger hits the send button. #3076 plugs are 7/8"-18UNS. That fourteen threads per inch thing is for fine thread 7/8" bolts, not spark plugs.

No more Dr Pepper for you.
Charlie II at
Moline Parts