Originally Posted by
Moon Dust
I asked TfL about this and they only care about the classification of the engine, ie is it Euro 4 or not. They don't test for emissions.
DVLA only require a receipt for the engine or confirmation from the garage that the engine was swapped. They don't require a test for emissions.
https://www.gov.uk/change-vehicle-de...idence-to-give
MOTs from what I can gather test for emissions against the oldest componant of the two, ie a 2005 engine in a 1995 car will be checked that it passes the emissions test of a 1995 engine.
Or have I missed something?
I understand an engine swap might not be straightforward. That's why I'm asking here.

Has anyone put or seen a Euro 4 or 5 engine in a 90s car (not necessarily for ULEZ reasons) so I can see what's involved?
Swapping engines on old Fords used to be fairly straight forward, the engine mounts and bell housing bolt holes would be the same but I am not sure how you would go trying to fit a much more modern engine. It could involve having to make new engine mounts, sump modifications to clear cross members , mountings for the catalytic converter and all the electrics, ecu and engine wiring looms.The costs will be high unless you are doing everything yourself and then maybe buying a good used modern Ford with an Ecoboost engine for example may be another option?