Flathead pontiac spark plugs

Anybody know which plugs to use in a 37 Pontiac 222 flathead six. It has A/C
R45's now.
Thanks, Colt

 

AC 45's are in the right heat range. You might try the AC 46 or 47 if you need something hotter. I have 1940's rebuilt plugs of the 47's at least , and also Champion J-8's and J-9's for the same temp range. $1.00 per plug plus shipping.

 

Thanks warbozz, If I can't find them locally I'll be in touch.

Thanks again, Colt