cast iron heads vs aluminum for stroked 340

The problem arises with X/J heads that already have the big valves in them, especially if they are the stock type valves. The seats and throats in the factory 2.02 valved heads are already screwed up. The valves go in the trash can and are replaced with 11/32 stems. The seats are replaced, both intake and exhaust and you get new bronze guides. There needs to be a plug built for one of the head bolt holes that goes between the intake ports and a longer head bolt used. So, you have new valves, guides, seats, heads surface milled, race valve job and porting. Eh, figure only $2,200. Then after all that, the ported Edelbrock heads are probably going to outflow your expensive iron heads.

You never run iron heads in a high performance application unless the rules require them or you just gotta have them 'cause you think they are cool.