Camshaft

["Chris C" <petleech@xxxx>]

We are trying to isolate a rough-running problem in our car. We 
suspect the injection system but have tried everything in our ability 
with no success. We normally do all the work ourselves 
but a bad back problem has forced me to give my car to a local shop. 
The local shop has told us that these engines are very prone to 
camshaft failure because of a poor lubrication design. Our car has 
82k on it. At what mileage do the camshafts start to wear badly and 
what are the symptoms? We did a compression test before buying the 
car and all readings were between 155 and 165psi. If the camshafts 
are bad are they difficult to replace and is there a solution to the 
lubrication problem? If this is a very costly procedure is it better 
to simply buy a good used VOLVO B28 engine? Is the engine from th 
volvo car identical to the DMC engine and does it mate directly to 
the DMC gearbox?