if u stick a 2.0 16v into a mk2 it will be quicker than ur 1.8 16v...all day long
my old mk2 16v was a standard model engine wise and put out 150bhp on rollers....and was easily beaten by a mk2 2.0 16v especily at high motorway speeds it pulled away much better but not so much that i could keep up and wip its ass on the twistys as my suspension set up was far better

...but a very good conversion and not to much work as long as you have a 90spec mk2 as wiring is different from early mk2 16v's ...
or as above just get 9a 2.0 bottom end..you will get bit more torque...
but if im honest ive never seen the point with a mk2 16v....i like them way they come....and if you stick a full stainless and 4-branch on a good valver and drill ur air box for better air flow bang a k&n filter in there you will easy get 160bhp ...and a valver with those mods sounds awesome on full pedal to the metal...
(ive just talked my self into getting another valver...god how i miss mine

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