Can any one out there help me. I want to build a 1948 Oliver 60 to pull in the 2500 to 3000 lb.  3 mile per hour and 5 mile per hour Classes. I'm going to port the head and bigger valves if I can fine some that will work. I will be shaving  the head to lower the cc's on it. The pistons are still stock flat top .30 over. Does any one have any good grind specs for a cam. Thank for help Wingate