Re: whats the diffence?????
the 140 silver black engine came out in 2001 and is euroIII.
The old 136 is only euroII and ran up to but not including Yplate typically.
There are a few differences, ECU, EGR and the type of turbo, the 140 and newer uses a GT2256 turbo which uses a vacuum operated module to open and close the vaines.
The old 136 uses an old VNT25 turbo - much smaller and I understand (but not positive) this uses a more traditional pressure operated system.
As for engine swaps between the 136 and 140, I wouldn't bother.
140-150 OK, and I should think a 175 20valve could be made to work happily on a 140/150 car with a few sensor mods and ecu remap.