tryna get close to 400 hp...Wanna work out my 973 casting 318 heads

I'm trying to pull maybe 350-400hp out of my 318.

I'm planning on KB flat tops to up the compression a bit but what should i do with the heads?

i know they're restrictive so im thinking i can have the shop mill it .050 and put bigger valves in it. Question is, do i go 1.88 or 2.02?? Then port match? Id try to find some 302s but my heads are brand new recon. so I know they're good

The cam i have is a Crane 272
http://www.summitracing.com/parts/CRN-15005/

.454 lift...i think that'll work out yea? Or should i sell it and go bigger?

anyways, any input would help out. These are my ideas, just wondering if anyone has different opinions on the set up other than going to a 360. lol

thanks