Stock sparkplugs are BF62. I used to run BF42 and they where fine; engine has head work [ported, valve bowls, milled for maybe 9:1, intake log work for 350cfm Carb], healthy cam and exhaust. Sparkplug numbers have changed over the years so I am lost. Last plugs I put in are Autolite #36, where am I [or should be] as far as heat range? Does one clean sparkplugs or just relpace? Sand blasting a no-no?
The Jalopy Journal
