I'd say its caused more by the tires than any kind of tune. For the idle check for vacuum leaks and make sure the inlet pipe is tight.My new 2004 Mach 1 is idling at about 1100 rpm and does burn the the tires 1 -3rd, so what gives? Is it tuned? Nastiest 4.6 I ever saw..., and that's after sitting in a field for 5 years.
It has a full k&n induction on it. By inlet pipe, are you referring to the throttle body? This is the 1st late model hotrod I've dealt with, so I'm not real bright on the terms. My rods are 60s show and go rides. Sorry.