Ok so I burn a good bit of oil in my 383. I can't remember if I always have or if it started after a certain time. Compression is good all around. Will overheating cause the seals to harden? I've never had a head apart but I do have some spare ones and a spring compressor to play around with before I try it on my 383. Now, an old timer up at work told me I could cut off a spark plug (the ceramic part) and braze a compressed air fitting to it to keep pressure on the valves and keep them from dropping (does that work?). Then I could take the springs off and... they're right there? haha. Now my dart heads have dual springs, is that going to cause problems? Also, I don't know if it was him or someone else that asked me either what kind of guides I have or what kind of seals I had and of course I don't know. What is he talking about? I know I need to figure out which type I have to order some more but this is a new ball game for me. From what I understand if the guides aren't worn then I can just replace the seals. How do I know if the guides are worn? Can you wiggle the valve and tell? Need advice!