426 Hemi Spark Plugs

[Wolfe440]

Have a stock recently rebuilt 426 hemi, I'm using the designated Champion RN12YC, engine runs good but eventually having some fowling. Thinking of going step hotter.

Anyone have more success with a different brand and heat range regarding the 426?  

Thanks, Wolf

[LaOtto70Charger]

No experience at all with hemis but my 318 always liked autolite 66. Champions fouled within a month in the past. Also check your pcv valve and air breather if you have them.

[Wolfe440]

No experience at all with hemis but my 318 always liked autolite 66. Champions fouled within a month in the past. Also check your pcv valve and air breather if you have them.

Pcv and air breather both bran new.

[LaOtto70Charger]

That is good. My car was fouling out plugs just warming up. Had to replace those, the gas, and clean out the carb. No longer blowing smoke and plugs look much better.