Champions are fine. These are not high tech racing motors. They are 4 bolt main engines which is great. They trace their heritage to truck engines, not race cars. 350 hp. from 454 cu.in. is not much better than your lawn mower. Don't get to hyped up about the little things. These are great engines that should last in excess of 2500 hrs. with reasonable care. The quadrajet carbs are a bit goosy, but Edelbrock makes a good replacement. Ours are stock and the only thing I have done to them is set the spring tension on the secondary choke plates. That isn't critical and you need a special gage to read the tension. Our previous owner had Prestolite solid state distributors installed and they are fine, but not magic. I change the anti-freeze every 5 years, oil every 100 hours, and spark plugs at 300 hours. I do adjust the idle mixture, but I have never really felt that it made any difference. Timing is important but should not change once set correctly. A little timing chain stretch or gear wear on the other engine will cause a little retarding of the timing eventually. I always check it when I change the plugs.
