For engines approaching 70lbs of boost. I have noticed that the ARP studs have a narrower shank than some others that I have seen. Do you have to match the studs to the type of gasket. e. g. a heavier stud for copper or a stud that streches more for the stock head gasket. One last question I have is do you torque a heavier head stud more or the same as you would torque a lighter stud. I would appreciate any input on all the different cylinder head studs available for the Cummings engine. Merv