I have a 68 383 4bl. 906 heads don't know what it come out of but i ordered a set of champion plugs for it and found out they are the long reach plugs and mine are the short reach autolite 85 . My question is why do some 383's use short and some use the long ones ? I don't think i can use the long ones they look like they would hit the piston ? Anyone know what the deal is ?
