s#*(&# f*&^)!! (my 318 rant)
seems strange to throw a timing chain after only 63,000 miles... maybe 163,000? Anyway, I'd pull the heads off to check pistons... look at the bores, etc... that way, you get a better picture of the condition of the engine...
Ding! Ding! Ding! Winner!
I just went through almost the exact same thing. I bought my Butterscotch Dart with a "blown head gasket". No biggie. After pulling the head, I find that I not only have a blown head gasket, but I also have dents in the tops of my pistons from the valves hitting them on the left bank. So I've got a bunch of bent valves. Timing chain was replaced by a PO. So I pop some new valves in it, lap them in by hand, and figure I'm good to go with a cheap fix (I pulled both heads and changed all the valves). After all, its got 85k on the clock and the PO said that's what it has on it. Plus, the car is super clean, so I figure its right on.
After putting everything back together, the 318 still runs like crap. I replace basically the entire ignition system looking for my misfire. Well, I should have checked the cam first when I had it all apart (my mistake), because after pulling the intake again the cam is flat. Timing chains in 318's last a long time (well over 100k usually), and so should the cam. 1+1= 185k on my car, and I should have just rebuilt it to begin with. Instead I'm out the time it took me to pull the heads and lap all the new valves, trouble shoot the thing for weeks and of course the money it cost to replace all the valves, valve seals, and all the gaskets for the intake, exhaust, timing cover etc, and it still needs a rebuild.
I'd venture to say your 318 has 163k on it. If you've got another engine to swap in, awesome. If not, I'd look at doing a rebuild on the one you've got. If it has that many miles (or its been abused that badly in 63k), you probably won't be happy trying to "fix it cheap" once other problems start to crop up.