[Venetian]

I am considering doing a top end rebuild in the near future on my 1987 Carrera(134000 km). Its consuming approx 1L per1000 km at best and I notice it is starting to smoke slightly at times at stop lights. Plugs were good last time I changed them except for one which appeared oily and black. Does anyone have any experience with rebuilds in Calgary ie recommendations?

May consider swapping to 3.4 L pistons and cylinders. Other than the cost, any comments in terms of performance and reliability?
Would other changes have to be made ie injector sizing? Has anyone done this modification?

I could probably hold out for quite a while yet before rebuild but I think its just a matter of time!