Reply to "Stock Brake Caliper Modification"

My second set is done similarly, although Wade (4280/Mark IV on this board) drilled the pistons from the inside of the cylinders. He drilled through the thinnest part of the wall using a specialized right-angle dentist drill-type arrangement, and a very short carbide bit.

The passage is approximately 3/16" (maybe 1/4").

This approach alleviates any minor concern of blowing out the setscrew, or leakage from the externally drilled passage.

These calipers were cleaned and painted, the pistons were polished, a new rebuild kit was installed, including the flat gaskets between the caliper halves.

Finally, instead of drilling the middle bleeder, a 10x1.25 Metric banjo with an A/N-3 fitting was used in the lower manifold input.

The upper bolt (silver in this picture) has an angled seat machined into it to seal against the standard flare seat in the caliper.

Here's a picture of the completed calipers (without the banjo).