How did this happen?, Nasty cam followers Options

[ThinAir]

As some of you may remember, at the end of April my son (Mike) and I flew up to Seattle and drove the Yellow 73 2.0L back to Arizona. Things seemed quite well for the first half of the trip. The engine ran strong and temps were right where we expected them.

We stopped north of Bakersfield to catch a few hours of sleep and when we restarted the engine it was as if some alien had swapped the engine while we snoozed. It kept backfiring out of the left carb. As we headed up Tehachapi, the temps went right through the roof and we limped back to Bakersfield to see what we could do. Eventually we figured out that the timing was too advanced and the valves were all very loose. Even though it was better, it was clear that #2 cylinder was the one that was backfiring out of the carb.

Once we got home, I pulled the head and had it checked out by Competition Engineering. They said the head is fine, it may be a bad head gasket - but more probably it is that your cam has gone flat. That didn't make sense to me since only #2 had problems and I would expect its opposite to have problems if it was the cam.

Well, tonight I finally pulled out the cam followers. The one you see on the left is #1 intake. #1 exhaust looks just as good. On the right is #2 intake. Besides being wallowed out, it has a slight ridge on it. #2 exhaust must have a bigger ridge because I can't get it out of the case.

It looks to me like these cam followers were probably not rotating and had not been for quite awhile before we started driving the car. It's too soon to tell about the cam, but I'm guessing it's gone too. What is clear now is that since #2 exhaust wasn't opening far enough, the exhaust was getting pushed back out the intake whenever it opened.

So... the question is, how does this happen? I've never seen such a thing before!