170 tdi engine in to a 140 tdi car?

[t51rjohn]

I think i know the answer to this question but thought you guys/girls can confirm with your wealth of knowledge.

I have a 2.0 140 tdi which has 170k miles on it. The engine is worn and needs either a head rebuild/bottom end rebuild or replacing. I have been advised the head needs sorting and will cost £1000 for the labour by vw to remove and replace without any of the remedial work. So this will be upwards of £2k by vw. I have had a quote by a local mechanic who is reliable and used for my other cars and any big work on this car. He quoted £1100 all in. Now i have a mate who can get an engine replacement fitted for £250 if i source the engine. This seems like the best option as i can fit all my injectors etc that have been replaced under warranty.

So with that in mind can i source a 170 engine and fit that easily or will i have to fit another 140 engine. I have recently been out in a mates 170 that was remapped and loved it so would like to fit a 170 if possible rather than a 140 and remap to 170.

P.S i have googled this and maybe its the wording i use but i cant find anything.

Thanks John