Originally Posted by mentalasanything

It all depends on the engine you have. If yo have a std ERST engine with no mods that is tired, then yes that would be an easier option.

But in most cases people already have some mods or a strong engine and would like to keep them, hence modifying the original.

Also if you were to exchange it with another engine you would "by law" have to inform the DVLA of the new engine number and in most cases they would want to inspect the vehicle at one of their offices to see the work has been carried out. As my Dad did when he replaced the engine in his old mk4, which he found a right faff.

Also wiring in an FRST EFi loom into an MFi RS Turbo isn't the easiest thing in the world to do.

Lee