See if any of these past threads helps.

http://forums.y-blocksforever.com/FindPost42903.aspx

http://forums.y-blocksforever.com/FindPost42909.aspx

http://forums.y-blocksforever.com/FindPost38509.aspx

Lorena, Texas (South of Waco)

Thanks Dennis I thought I read somewhere that it should stay at factory specs of .019. I appreciate the response. Dave

SE Wis

Should be .015 hot.

  Dennis in Lititz PA

Looking for recommended valve lash on newly rebuilt 57 312. Block is .030 over, zero decked, heads milled .010, which makes it close to stock compression ratio, cam advanced 4 degrees, flat top pistons, B intake and 600 Holley. Building mainly for low end torque. Dave V

SE Wis