Hi all

Looking for something stupid good on fuel for a daily. The original 1.4tdi 75bhp I'm well aware of. However wanted the Newer eco one as its claimed to be nearly 20mpg better, how? It looks same engine in specs yet it has 70 or 80 bhp. Has the engined changed? Or just been mapped? They come with dpf's I know but army trouble some on this engine. I had a 170 2.0tdi so know all about those problems.