I have a 69 F-100 with a 300 six,was bored 30 over, I put headers and a offenhauser intake with a 390 cfm holley carb with a mallory dist and coil. What plugs should I be running in it.Should I run a stock plug or use a hotter plug. Thanks

 

I recomend the stock plugs.

 

I have heard here that the plugs for the fuel injected engines are supposed to be an up-grade. Hope I'm not confused OBCB