Scat Pack 4 piston Brembo calipers and rotors
Ear mount calipers are a royal pain. It is so much easier to use radial mount calipers. The mounts are super simple to make and they are very strong.
The radial mount bracket is very simple to design and build and it is very strong.
I agree the radial mount calipers are much easier to get located correctly both at the circumference and centered over the rotor thickness. But I'm not sure I agree they are simple or easy for someone without their own machine shop to make. I can't imagine trying to build something like you show in your second picture with a drill press and a grinder. :D
Even with the advent of online machine shops, it still isn't a cheap option. I've got a single '03 Viper rear caliper I messed with and 3 years ago it was going to be $125-$175 per bracket to get a couple of brackets machined from Xometry. I don't know what it would cost now, but the bracket for the ear mount caliper was $85 each last week. Not necessarily an apples to apples comparison as I don't remember what material the radial mount bracket was quoted as.
I will add that the ear mount bracket above was a breeze to get the caliper located correctly once I got the holes located. Not sure on the "oddly shaped and too weak" criteria though.
All of the higher end cars use radial mount calipers so there is a really big supply to pick from.
There might be a good supply, but they aren't cheap. At the same time I was looking at the radial mount bracket for the Viper caliper I have, it was about $300 for another remanufactured caliper to make a pair while the Scat Pack calipers were about $240 for a pair. And a pair of Mustang GT Brembo's were about $260 a pair. Right now the only source is used as far as I know. BTW, the one I have is brand new, never even had brake fluid in it.
I know there is a "Viper tax" so anything with Viper in the name is going to be more expensive, but generally there is a tax for all high end cars as well. Either way, I did look around and couldn't find anything that was reasonably price and had pistons big enough to be usable.
Funny thing was, last week RockAuto had Scat Pack calipers for $18 for one side and $57 for the other. But those are gone now. At the same time you can still get reman's for as low as $121 each and they list new ones for $158 each while a single match for my Viper caliper is going for $330-$725 on eBay right now.
The thing that really opened things up for me is the option for laser cutting flat plates from online sources. The cost for all the plates for the Scat Pack calipers (both sides!) was less than a single radial mount bracket, and I went way overboard with the plating. Bare, I could buy 2 complete sets for less than 1 radial mount bracket.
I've got 5/8" of steel supporting the caliper, 3/8" on one side and 1/4" on the other, so I think it is plenty strong. And not cantilevered like the failed aluminum bracket I referenced at the beginning of the thread. If I had drilled the threads out of the spindle, I could have used any thickness I wanted on backside of the spindle.
The only drawback I can see is that using off the shelf flat plate thicknesses means the caliper will need some shimming to get it centered over the rotor. In this case the calculated shim thickness is 0.0547" which is more than I would have liked. This what you are saying in that an ear mount caliper spacing is not the best, I agree. But I have to point out that at least all of the big dollar kits that I have looked at that use radial mount calipers include instructions for shimming the caliper bracket to get the caliper centered over the rotor. So I'm not sure the radial mount calipers really fix that.
If I was marketing this and trying to make this setup the absolute best it could be, I would drill out the threads in the spindle, make the outside plate 5/16" or 3/8" and get a single cut done on a mill to make the thickness of the plate where the ears mount match what is needed. Best guess, the outside plate would be maybe $50 each from Xometry while the rest of the plates might be $60 (bare) from SendCutSend. So $160 for a set of brackets to mount a pair of $300 Brembo calipers. Not back in my mind. Certainly the low end of the fix caliper market, but a reasonable path for someone budget minded like me.
