Chevy Guru's chime in...

[quote=“J&J,post:25,topic:38069"”]

Lots of good info in this thread. It all comes down to your budget and what parts you have already. Rich Krause mentioned a GM crate engine which are serious bang for the buck. If you already have a stout short block you can’t beat GM Vortec iron heads, 10.5:1 compression and the right camshaft to match your combo

[/quote]

Listen to that man! The Vortec heads are damn good and cheap. PN 12558060 is available fully assembled for ~$275/head.
[FONT=Univers-Black][SIZE=1]
[LEFT]12558060[/LEFT]
[LEFT]Cast Iron Vortec Cylinder Head Assembly[/LEFT]
[LEFT]• Completely assembled with 1.94”/1.50” valves
• Uses bare head 12529093
• 64cc combustion chamber
• Straight spark plugs
• No heat risers
• Requires Vortec specific intake manifold
• Camshafts with more than 0.475" lift require machining
valve guide bosses and checking valve seal to valve
spring retainer clearance
• Can be machined for 2.02"/1.60" valves
• Rocker arm studs can be pinned or drilled[/LEFT]
• Valve spring seat diameter is 1.48"
[/SIZE][/FONT]
The bare head PN 12529093 is nearly the same price. Go figure GMPP’s prices??? But even if you upgrade the springs, you are still talking less than $750 for a pair of really good heads ready to bolt on. With a decent cam, intake, and carb these heads are good for >350hp.