I've got a German language sales brochure for a 128 Abarth. It had the leather Abarth steering wheel, twin pipe Abarth exhaust and alloy Abarth road wheels, plus body striping and I think a tachometer added to the top of the dash, plus Abarth gear knob. In the late 1970's you could get a whole range of Abarth accessories, marketed in the UK through " Abarth Action Stations" ! They did a little sales brochure and I bought a twin pipe exhaust back box for the Fiat 1283P which I was driving at the time from Bloxham's of Wolverhampton. I think the German 128 Abarth was a way of tarting up the standard 128 to make it more saleable. I don't think the engine was modified at all.