Depends on maintenance.
Should all crack 200K though without too much trouble.
Compression and bearings might be worn depending on how frequent the oil changes have been done.
But Technically speaking its a simple Double over head cam with on phase adjustment.
So its about as simple as an engine can get. No turbo so oil isn't chewed up. Uses standard injection points in a sequential manner in the inlet manifold. So again pretty reliable.
just over time it will loose power and before less effcient. But if you change oil at 6K, keep topped up and make sure you use a decent filter it should keep going.
My first engine made it to 112K but the last 7K driven by me where quite hard on the small engine.
However there are other's in here on double my mileage on the stadnard engine clutch and gearbox.
I'd say all engines these days should crack 200K miles.
Alfa 166 2.0 Twinnie - LPG and a few trick performance parts