Hey guys I wonder if you can help me, A friend of mine just had a 406 small block built for his car, the problem is it idles the best when the initial timing is 40 deg adv.? if we back the timing down to about 18 deg it runs like crap and starts running hot and clattering, what could be up with this motor everthing is new, msd vacuum advance dist, 6al box, Initial timing was set with the vacuum advance plugged, any suggestions?
thanks jeff