After two weeks of busting my ass I got my freshly rebuilt engine back into my 914-6 track car and hit the track yesterday to break it in. After a successful first 25 minute session I headed out for my second session. As I was pulling into out today I hear a clunk. I pulled o we and went to apply the brakes and they went to the floor. This is why....

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Ive not yet determined what happened. Perhaps a stress crack that finally let go? Thqts one thought, given the metal where the break occurred is dirty and not clean like you might expect in a fresh shear. The lower bolt is still threaded in to the upright, albeit bend from the caliper breaking off. The upper bolt is nowhere to be found. If the top bolt was missing for some unknown reason could it have trigger this?

Good news is that this happened in the pits and not on track. It could've caused a lot more trouble.

Heat and too much torque? Glad you are OK...

Wow! Ya looks like it has been that way for some time. Lucky day!

I was definitely lucky it happened when it did.