Brian S

Guys,
Whether it's head bolts, or wheel studs, how you get to usable clamp load is about the same. There is a reason that most cars have steel wheels. The reason is, because steel rims are made so that they provide a spring effect, very much like a lock washer. It's very easy to get enough clamp load, by just about anybody, even with a crappy flat tire wrench. Sand cast or die cast centered aluminum wheels, or completely cast wheels, have one thing in common. They all have air captured in the cast aluminum. Unless they are vacuum cast, which is expensive, air is present. Air makes the aluminum less dense. Where as forged centers or forged wheels are much more dense, more solid. Forged wheels also have the ability to bend, as opposed to cracking. Cast wheels will have their wheel nuts bed in, a little like the steel wheels. Forged wheel will not, so they require a higher torque. The harder and denser the material the higher the torque, if all things are equal. Wheel studs are all about the material, OD, and how fine the threads are. Fine threads are stronger than coarse threads. It's pretty easy to say that any OEM wheels stud/bolt has way more engineering in it than any aftermarket fastener. The bigger the wheel, the wider the tire, the higher the load, higher the cornering speed/load, all would effect the clamp load required.
Hope that helps
Brian S