The first exhaust valve you show looks like it has a piece missing from it. So either you have a bent or burnt valve. Is your car a turbo or non turbo? Abscate our moderator has recently had a mishap with one of his P80 wagons. He looks after his cars so I believe he may be parting it out. Might be ...

hi my guess would be whomever fitted the cambelt got the setting wrong and either ran it like that or forced engine to turn when locked up by a valve open hitting a piston near tdc maybe this was the case and they tried after to reset the marks,wouldnt be the first time id seen this at worst a valve...

It depends on the cost of a good known used engine v's the time, labor and parts to fix a cylinder head. This is what I was talking about and you would be lucky to do a rebuilt head for this amount! https://www.matthewsvolvosite.com/forums/viewtopic.php?t=103275 Abscate rebuilt this head less than 1...

Another round of sea foam and you will be good

My guess is you had sticky valve guides and they are freeing up

Since there was a marked increase in compression after the first round of magic juice, it could be stuck rings. Seafoam will help a bit - it is widely reported on other forums that the secret ingredient in that stuff is odorless kerosene - my suggestion would be to follow that with a dose of oil; th...

If the car has been sitting for a while, then it may develop a tick. Once it has had a decent long run it may well settle down. It sounds like the 850 I worked on recently with over 300,000 miles on it. It had been sitting for a couple of months or so and sounded like a bag of nails on first start u...

It can take 20-30 minutes for the lifters to fill with oil after a dry start. Volvo says to keep revs under 3000 rpm until the clicking stops, source: owners manual.