I am planning to go through my 1.7L in the near future, and have a change to pick up a cleaned up 1.8L crank that is re-ground down 10 thousands dirt cheap. Are the 1.7 and 1.8 interchangeable, or am I better having my 1.7 checked out and cleaned up?

Thanks for the input.

crank is the same and although teh rods look different, teh journals are teh same size also. 1.8 rods have a bigger bump on teh small end