kwick fit puppets........
theyve split/cracked a pipe, or not fitted one properly, thats deffo your prob jason, its all a matter of finding the fecker!!!, sounds like it might have a blockage on a breather somewhere for the oil thing as i reckon its blowin some out into the airbox when you rev it hard, i cant see it being valve stem seals, as they smoke lightly all the time then progressively get worse, and the mileage is low on the car for its age and its been well looked after and had loads spent on it. so tis split/broken pipe/or pipe not on properly for idle prob, and a breather prob for the smoke/oil in air box prob....... like i said before jason, id have a look and give you a hand, but ive got a busted leg and your 400 miles away!!
Gaz