Which heads on 1994 magnum block

milo123 said

Have a 1993 dated magnum block going in a 1971 dart. Speed pro h116cp pistons, undecided cam yet. Both heads were cracked like normal. Trying to decide if should go with speedmaster aluminum heads or get some magnum replacements. Block has the oiling for la style heads. Would like to be around 400 hp, or little more. What would be the best and easiest route? Is there alot of geometry issues with the speedmaster heads? Is there any good flowing magnum cast iron heads available anymore?

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Currently, there are only China stock replacement cast iron heads available.

Edelbrock makes and aluminum Magnum head that uses Chevy small block rocker arms. This lowers the rocker arm cost a little but the cost of the heads makes that a factor not worth considering. This head has Magnum intake bolt pattern, so pretty much an Edelbrock dual plane air gap intake is best choice.

The Speedmaster aluminum heads are pretty much a copy of the Edelbrock Performer RPM LA head, so geometry issues are similar on both as stated in post 4. These heads have LA oiling allowing LA rocker arms. they also have LA intake bolt pattern allowing more intake options as mentioned in post 4, but again and Edelbrock dual plane air gap is a good choice.

Editing to add: The smaller chamber of the Magnum style Edelbrock head will give about half a point higher compression ratio with similar head gasket specs used. Again, not a deciding factor at this level, but more info.