I'm installing a set of front brake calipers on my track car, and the mounting brackets are made of aluminum (7075). What is the better mounting scenario - Thread the mounting bolts directly into the aluminum, or use a through hole mounting method with a proper bolt and nut combination? The bolts are orientated perpendicular to the brake disk, that is, they would be loaded in shear. If I thread the bolt into the aluminum mount, the amount of tension I can preload the bolt with depends on the aluminum, as I'd expect the threads to strip before the bolt yields. If I use a through hole, I can tension the bolt properly. If I mount the bracket using a through hole, would the bolt need to fit very tighly on both the knuckle and the mounting bracket? Is there an issue with applying to much tension to the bolt and causing the bracket to deform? I should mention that the OEM caliper mounting bolt is M12 x 1.25 x 21mm and goes through the mounting tabs (10mm) on the knuckle and threads into the bracket. So it only engages about 10mm to 11mm worth of threads on the bracket. That is the main source of concern for me, especially in an aluminum bracket. Finding longer bolts of equivalent quality has proven quite difficult (if anyone has a source, please let me know, I need something about 25mm to 30mm in length, partially threaded, 10.9 or greater, flanged head preferrably). The alternative mounting scheme would be to go with an AN or NAS bolt, 7/16" in diameter. I would use a 1/2" bolt, but I do not want to bore the mounting holes in the knuckle. I would make an appropriate bushing for the knuckle that would be a light press fit with a 7/16" ID. I was also considering making the bushing with a flange on it so it also acted like a washer. I could then either thread the 7/16" bolt directly into the aluminum mounting bracket, or I could use an appropriate nut on the other side of the bracket. Another possibility would be to make the bushing extend into the bracket and make it a press fit into both the bracket and the knuckle. Keep in mind the wall thickness of this bushing would only be approx. 0.021", so I don't think there's much strength in the bushing itself. I am likely overthinking this, as the caliper is a radial mount with 3/8" studs that thread into the bracket, but since the bracket has yet to be machined, I'd like to make it as stiff and as safe as possible. BTW, if anyone has equations that would help me, I would certainly appreciate it. ME is not my forte, but I'm certainly not afraid of any mathematics. In fact, I would welcome it, as I really want to understand the forces involved, and I'd like to convince myself that the mounting scheme I choose is safe. Thanks!