[SuperMacGuy]

I was at Summit Point yesterday for FATT. During my 2nd heat I had my left front hub fail. It let loose in turn 5-6 or so, and if you know Summit, that's about the slowest part of the track. Which is right after the part of the track with the highest pucker factor IMO (downhill at 80-100 depending, about a 30 degree turn a little off camber and max braking soon as you're through it). So I am OK and there is no body damage.
The hub flange sheared right off, and the wheel getting pushed back it must have bent up either the brake caliper or the slide pins, the caliper doesn't float any more. A guy with a TA next to me thankfully had a spare hub, so I got that on and drove carefully home. This was a Mike Minear hub so I'm contacting him to see if he wants to inspect it. I'll probably get a new one from him over the winter.
I'm thankful that was all relatively low drama. If that happened almost anywhere else on track, well all the other places are pretty high speed, and it would've been a real wreck, literally.

Chris

[00 SS]

I have some dye penatrant on order. I'm going to do mine soon provided I can get the ring mentioned above off. One of the broken ones is at a metalugical lab now for analysis. The analysis is being done as a favor, so I don't know how long it will take.

So far we know a couple basic things:

1. This particular unit had cracks start in at least two places.
2. The hardness was slighlty below the design target.

Hopefully, further testing will reveal more. Once I know all the test results, the design will be modified if the testing shows a clear path to improvement. That could be one or several changes including induction hardening intead of through hargening and/or minor dimensional changes.

The location of the break is the same size as a Dana 70 axle shaft and made of stronger material. These are used in heavy duty trucks that see loads far in excess of what an F-body can create. I am confident that the cause and solution can be found.

This post has been edited by 00 SS: Nov 13 2010, 08:33 PM