Costjo- You got things a little backwards - get a solid tune up before you start trying to look at your plugs and listening to your valves. Get a valve adjustment compelted, then do a complete tune up including timing setting. Get all the majors completed and then start with your SU adjustment. Reading plugs should be last on your list. The first thing on your list needs to be to read as much as your can if this is your first Z. There is a lot of knowledgeable folks on this site that enjoy sharing their knowledge, but you got to help yourself first by digging into research (just like all of us have) to learn how your Z operates (or find a skilled mechanic). Keep us posted with your results.