boring my 318

If that's your goal, then head over to pick-n-pull in San Jose and find a set of "...302s" on a Chrysler New Yorker ( '85 era ) and have them rebuilt from your local machine shop with the larger valves. I know that American Cylinder Head in Oakland can do it for you, but I'm not sure what shop in San Jose can - there should be a few. You may find a Magnum Motor in a truck if you're lucky, and it would be a good idea to pull the whole thing, 5.2 or 5.9L.