Spark plug help 9.5:1 532 d3 iron heads,

Need a good starting point. Msd 6al box, duraspark distributor, 830holley vac carb, performer air gap intake, hydraulic roller camshaft ,headers, 4.3 crankshaft, 5 spd transmission, 4.10 rear gear, weekend street use only in a 67 ford f250 2wd truck. Won't be towing anything as it's a frame off resto mod.

Thanks
Travis

For the street engines I build with those heads I use an Autolite AP24 but, the regular 24 should work.

Thanks Randy. I've never had an iron head pump gas motor and wondered about what plug and range with an msd ignition. Much appreciated.

Travis