Bolt Torque Calculator - Engineers Edge Engineering Calculators
This calculator seems to imply that clamping force can be determined by only using two variables, that being torque and diameter of the fastner. Most charts and calculators seem to follow this same pattern.
What I'm seeing from the data in the chart you posted is that finer thread pitches will have a higher
maximum clamping force, which I don't disagree with at all. But the graph doesn't show any different clamping force for same-diameter bolts with different thread pitches, just different diameters.
Now, I'm not arguing that it does, at an absolute level, exist as a factor, but what I'm reading seems to indicate that it falls into the noise of friction variation and certainly, in the case of lugnuts, the real world variation of even a calibrated torque wrench. In other words, you might find it an interesting exercise to figure out the difference, but it's not going to have a practical difference in how you tighten the wheel up.
Here's one for you though. Do you torque your wheels with the tire on the ground or in the air? If you do it on the ground, you're seeing variable forces from the weight of the vehicle acting unevenly on the studs. If you, for instance, tighten a lug nut to 80 lb/ft with the vehicle on the ground (use the lowest nut), and then jack the car up and hold the wheel in place (do this with a rear wheel with the handbrake), you can see a noticable additional rotation before the wrench clicks.
I've worked with racing teams that required all torqueing of wheels be done with the wheel off the ground. I've worked with others that just hit it with an impact until it "sounded right" too