[markjohnson]

There's no need at all to spend crazy money to try to get a set of old Closed Chamber 842's to even come close to a modern set of Open Chambered AFR's. That's just never gonna happen. With your 842's you should concentrate on some bowl blending, port matching, chamber polishing & CC'ing, a good valve job and a good set of Manley 11/32 stem valves. This work along with the proper factory piston dome configuration and head gasket thickness and you'll make fine power. You'll get the most bang for the buck with these mods. Open Chamber heads are superior to Closed Chambers but that doesn't necessarily make them junk. NHRA A/Stock '69 Camaros have run high 9's with Closed Chamber heads with no porting, so they are capable of laying an impressive number down.