Well not sure what to do ,I had some closed chambered ulp heads and hirise manifold coming my way but whent sour. So all i have is some open chambered 351 heads ,im debating if i should put harden valves in them or get closed chamber ulp heads , is there a lot more extra compreshion in them?

Allso were is the shop here i can take my thermo quads ,rockchester and 350 holley and trade them in for a 750 hol (lol)