Early 1600's were plagued by a 'splitting crankshaft' problem, because the front end was engineered down to too small a circumference.

In use, the slide-pin (to hold the pulley), would crack away the edges of the crankshaft - characterised by a knocking sound on idle, which came and went.

Proper repair for this is VERY expensive - cheaper to buy a short engine.

Problem was resolved within two years by an engineering change, machining a larger circumference on the crankshaft, but it's impossible to tell without taking the pulley off!

Since the 1600 was quickly 'de-tuned' to make the 1800 look better when that came out, 'later' 1600's were gutless.

A MUCH better deal is to simply go for the 1800 to start with - its virtually bombproof.

Make sure to change the timing belts at 60,000, but don't 'over-worry', the electronics will prevent catastophy if the belts loose tension (although performance is severely limited!).

Use high quality plug leads - expensive, but they make a BIG difference, and last virtually the life of the engine.