Finally got things torn apart and I think I know why my timing belt imploded. I noticed some dings here and there around the crank sprocket. I figured a screw or something possibly fell down and chewed up the belt. Upon closer inspection it looks as if a tooth actually busted off my crank sprocket. It's possible that a foreign object busted the tooth but the chances of that seem less likely. At least this explains why my timing belt blew 30k miles early but I've never seen a sprocket tooth bust off like this before. Has anyone else seen this?
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The mileage is just a recommended interval, not unusual for things to go wrong before or long after. Also its usually not the belt that snaps, but one of the supporting parts that fails, as is the case here. Any valve/cylinder damage?

 

I forgot to mention I did the timing belt service about 29K miles ago. The timing belt was probably still in good condition. Have you seen a gear spontaneously bust a tooth on a rubber belt?

 

Oh wow, that changes a lot lol. I've never seen a tooth just shear off like that before. Did you check the cylinders/valves yet?

 

Sorry, I was wiped out last night. The valves are shot. All the valves have a nice roughly 45 degree bend. I bought a remanufactured head which is going on in the next couple of days. The head shipped was $820 which to me is better than paying a shop to machine it for $600 and then have to replace the valves and hope everything works.

 

That really sucks! I have not seen a single tooth break like that but what might have happened is, because the crank will continue to rotate after the TB broke, it (TB) wedged between the sprocket and something else causing the broken tooth? How fast were you going when it happened? Any other indications of what might have caused the belt to break? Did the tensioner and idler look OK?

 

Everything looked good, it was all replaced about 30K miles ago during the service. I was cruising at about 40 in 3rd gear. I stomped the clutch as soon as my car lurched but all the valves were destroyed.