These heads were hot tanked, rebuilt, seats ground, heads milled, new valve guides, etc. Ready to assemble with your parts. They have the steam holes required for the 400 SBC engine. Painted Chevy orange with POR 15. Intake and exhaust have been ported. Both heads lost a valve or piston years ago, but have been milled and good head gaskets should seal. See pics. Original 1.94 and 1.50 valves replaced and machined for larger/better performance 2.02 and 1.60 valves. Do an online search about 441X GM heads that were only built for 2 years. Considered a very good street performance head when stock and these have been modified with porting and larger valves to improved performance more. These heads are getting hard to find and are a great upgrade for your 400 small block Chevy engine.