[g&gmiller]

hi all,
i know this may be a tough question without knowing how the engine was built and what was put into head work and cam but we took plugs out of my fathers cobra that were motorcraft asf52c and they were all black. it doesn't have a monster carb on it but it does have a pretty "lopy" idle. it is a 351 W. does anyone know or recommend a good plug to start with?

thank you
g & g miller