reliable engine rebuild

I have what I believe is a stock 1600 engine in a CMC that I purchased without any history. It's puffing a little oil when I rev it so I want to do a mild and reliable rebuild. Maybe pistons and cylinders and a valve job. As I search for the new parts, I see that some need machine work on the cases, I don't want to do that, but maybe a little extra power would be nice. If I stay with the stock carb, what size, or over size P & C's can I just bolt on without other modifications and still be reliable. Thanks

Without knowing condition of bottom end you might be wasting time and $. Why not hone current pistons and re-ring (if no scratches or out of round wear) and get a good valve job? This will give you chance to measure exactly what you have. Older P&C often are better quality than new ones. Find another engine that needs rebuilding and rebuild it while you drive the other. Add Peritrox ignition and good exhaust at same time.

To answer your? 87mm are slip in (some 88mm are slip into but not recommended for long distance/heavy use due to thinner C side walls). I have an old set of German Mahle ones that I wounld't hesitate to use though.

puffing oil? First thing to do is check your oil level, is it over the HIGH mark? Change the oil as well, is it new oil?

Chuck; as Wolf says 87 mm would be your magic number; you could use 88's but the cylinder walls are thinner and thus less reliable. Pick up John Muir's "Idiot" book and it tells you how to remove pistons & cylinders and measure the freeplay of rods and crankshaft to ascertain if your car is under factory tolerances without having to tear down the shortblock. If you find your shortblock is withing factory specs it tells you how you can go ahead and get your heads reworked, clean up the shortblock inside and out and just do a top end rebuild.

I have the book. Need it?

Ricardo, this sounds familiar! just like project X

You guys have no idea what a project x this is, imagine a speedster that a guy with little mechanical aptitude has, decides to take it apart, misplace a bunch of parts, loose interest, lets it set in a garage for 3 years, leaves his wife, and she sell it to me ....for a song. I'm not even quite sure if it is a CMC, it has thick chrome windshield posts like some that have side windows. I would love to post a picture, if I can figure out how to post a picture on this site.

Chuck, there are probably a lot of kindred spirits here who can identify. My jalopy, for instance, also survived a divorce. And, I'll be the first to admit, I started this thing with little to no mechanical aptitude! You'll have as much help as you ask for in sorting that car out, and lots of advice!

Cory, I don't buy the part about " no mechanical ability" . You probably had it but didn't know it.

Uh, Bruce, can I get away with "The Bug taught me humility."?
I know what a metric screwdriver is now, though. It's the one that slips about one milimeter past where you needed it to be when you used it as a chisel ...
And a metric wrench is the one that gets a full meter's arc on its way into the chassis with undue force. Love the car. Hate the learning curve.
Glad to be on the rebuilding part of the project.

Chuck, as Jjr says your motor sounds like project x; an engine he's got and hasn't run for close to 20 yrs. and we were planning on rebuilding. Do yourself a favor and get that book; it'll take you step by step in a very user friendly way....