Mitsubishi Repair: Eclipse smoking and staying out late, intake hoses, valve seals

Question
1997 Eclipse 2.0 turbo DOHC GS-T Spyder auto transmission 109,000 miles

 I have a problem with this car bellows smoke (oil) about 1qt per hour. I found evidence of alot of oil in the innercooler and intake hoses to throttlebody. So I had the turbo rebuilt and cleaned excess oil from intake pieces/parts.
 I also found excessive amount of oil discharging from all four exhaust ports.
 Checked plugs, very little evidence of oil, and good plug sign. Compression test shows 148 #4, 150 #3 150 #2 & 152 #1 cylinders. I removed (and replaced) timing belt and both cams to perform leakdown test that shows less than 10% leakdown / blowby on all cylinders.
 I have changed the air filter, PCV valve and hoses, cleaned the valve cover (welded up one crack around 1 mount bolt, still have one crack that does not leak)Could this crack be producing air leak to cause this problem.
 Beside the engine smoking it runs excellent. I have spent two late nights working on this problem, have you ever heard of such? Where / what is causing this oil to be discharged? Next guess would be valve guide seals? If you have heard of this problem before any help would be accepted

Thanks in advance,
Mac Clayton
Pearl, MS

Answer
Mac,
Your engine compression looks like it's right on.  The main areas where oil is lost and burns up is from valve seals, valve guides, piston rings, and though the spark plug seals on the valve cover gasket.

Most of the turbo Eclipse have cracks on the valve cover.  It's a pretty common problem. If you're finding oil on your spark plugs, you'll want to replaces your valve cover gasket.  Get the OEM gasket from the dealership.  It's softer and makes a better seal then the aftermarket valve cover gaskets.  Don't forget the little half moon gasket as well.

If you continue to burn oil, then it's probably time to remove your cylinder head and have it rebuilt.  You'll want new valve seals, valve guides and get a new head gasket.  Have the head resurfaced so it meets up smoothly with the block when you reinstall it.  If you're still losing oil after all that, you may be looking at a cracked head or block.  But check the easy and inexpensive stuff first.
Good luck!