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Hello- Just to clarify something... Because the factory torque spec for an 8mm stud is 18 ft-lb and for a 10mm stud is 23 ft-lb, many people draw the incorrect conclusion that the 10mm ones have a higher preload. They think that the 8mm ones are too weak to hold. This is absolutely false - they get the SAME preload! What they don't realize is that the emperical approximation to relate tightening torque (i.e. how hard you are twisting the wrench) to actual preload (i.e. how hard the stud is holding the things together) is: Torque = PreloadForce x ThreadDiameter x Coefficient While determining the exact coefficient is a rather difficult task (it depends on everything!), it doesn't take too much effort to understand a general trend here: the bigger the bolt, the more torque needed to get the same preload. And, look at this: 23 ft-lb * (8mm / 10mm) = 18.4 ft-lb. VW specified *approximately* the SAME preload for both kinds of head studs! Take care, Shad Laws LN Engineering - Aircooled Precision Performance http://www.lnengineering.com ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org