pcmhacking.net

It wasn't idling
The exhaust valves are liquid sodium filled and have a habit of losing their heads on contact and making a real mess of the combustion chamber and pistons, but they look to be in one piece still so as long as there's no piston damage then it'll just need a new set of valves and cams.
Not really sure why it happened - I was driving it a couple days ago and nothing has changed except the alternator...
Kind of regretting changing the cams over now

you just can't win!! hopefully its as minimal damage as possible!!

4 bent valves, but the head is r/s due to a lunched cam journal
Pistons and liners look ok though...

nasty!

didn't you have another head ?

Yep, but 7 of it's valves don't seal, and it needs injector reliefs cut into the inlet ports so no quick head swap for me...

ahh right, well ..... burn it

Camshaft: Cam sprocket has shifted - tabs bent and the lock bolt is probably in the sump Rear exhaust cam journal chewed out: Head off, cams out - spot the bent valves... I've got the head off my spare block and valves out - guides are r/s but the seats look like they'll come up ok.
The valves didn't look too flash when they came out, so I'm now considering a decent porting and big valve setup rather than just slapping it back together, but will depend on finances...

7 months later, I've finally made a bit of progress

New head decked, new guides, seats cut, slightly hotter cams ready to go: Almost there...

I haven't been able to do much with the alfa since getting it running again - my new house is in a quiet, respectible suburb and just starting the engine gets me scowls from the neighbors
But today I noticed that my bike's muffler fit nicely on the end of the alfa's exhaust - and although it's still loud, it's quiet enough for me to idle the engine in the garage without getting the cops called This meant I could get the engine up to temp and check a few things out finally.
All looked good, no leaks or overheating - there was a horrible metallic noise which I tracked down to being valvetrain noise being amplified by the plenum - if I put my hand on the plenum it stopped resonating and the sound went away

I gave my datalogger a bit of a test, I'm pretty pleased with how it's going but I still need to sort out the decimal point for the bignum font - it currently displays as a zero. and I finally got around to mounting my tacho

she looks good!