Yeah yeah, I know. They are crap, but I need to get this truck running. Compression is good, so I think the valve seals are bad. I can replace the heads or have them rebuilt. So my choices are a set of Vortec's or rebuild the stockers. Oh, the symptoms are it smokes slightly at start up, but after 5 min it starts to smoke heavily at idle and Spy Hunter style if you drive it. Compression is 145 average on all 8 holes with the lowest being 138. PLEASE let me know if you think its something other than heads.