I agree. I changed from dino oil to mobil 1 full synthetic a couple of years ago and noticed an immediate difference in performance with my old 289 that had 230K miles on it at the time I switched. The price of dino and synthetic is virtually the same considering you can put twice as many miles between changes using synthetic. The filter makes a difference too. After a lot of research, I chose the Ford Motorcraft filter. You can go to my FAQ section at the top of the Classic section and read the oil filter study. Royal Purple and Amsoil are excellent synthetic oils, but not much better than Mobil 1 that you can get at Walmart. Get the idea out of your mind of using a blend. You don't want to use any internal cleaner, because you run the risk of breaking off black gunk and stopping up oil passages. Just switch to synthetic. You may get a little leakage at the gaskets at first because the synthetic is so much slicker. But, that will stop when the old gaskets swell back up. I use Mobil 1 10W30 with great success.
