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I bought a 95 mx3 1.6 that had previously broke a timing belt, and the old owner just put a new belt on. It ran and drove, but was underpowered. I drove it about 6 monthes like that, then did a leakdown test which revealed a destroyed exhaust valve on #2 cylinder. I took the head to a machine shop and had the valve replaced, and the seat cleaned up. The shop did a valve job and installed new valve seals. I reinstalled the head using mazda gaskets, as well as a mazda timing belt, and water pump. The car ran and drove MUCH better, but started blowing blue smoke for a few seconds at startup. This progressively got worse, and now even after warm up if the rpms are over 1800 you get a major smoke screen. I did another leakdown test and found no problems, so I did a compression test and got 172 176 176 180 and wet got 174 176 178 182. I thought I had a ring problem, but testing didn't support that. So I bought a tool and replaced the valve seals with the head still on. This was way more time consuming that It should have been, but would have been worth it, except it didn't fix the smoke. The smoke is blue, very bad at startup, then goes away at idle, comes back at 1800 rpm and up. Burns about a quart of oil every 10-14 days. No smoke before head job. What am I missing???

Your head gasket might not have gone on correctly. It could have shifted a bit (allowing oil to seep through) or it didn't set correctly. This would also cause oil to get into the cylinders. If you can't figure out the problem, take off the head and check the gasket over. Make sure there was no gunk on the gasket, head, or block creating an improper mating surface. The gasket could have also been defective as well.
Even though your compression test did not confirm bad rings, they could be sticking and not floating like they should. The floating allows the rings to scrape excess oil of the walls. If they can't do that, then oil can get left near the top of the cylinder walls and getting burnt.

Hope this helps.

Yep oil is getting into the cylinders, and I agree with what Savin says. I'd buy a set of gaskets for the head and piston rings, take the head off, hone the cylinders, replace the rings, replace the head gaskets, and see if that solves the problem.