i presume its worked out as a percentage of cars made that are written off rather than straight numbers so 5% say of leons might get written off being say 50 cars whereas 3% of focuss get written off being 300 cars (numbers are just plucked from thin air and bear no resemblence to sales figures)
if you pay anythink like that for a fiesta st youre being ripped iirc the people i know with them payed approx 11k with leather
the st will fairly easily (zaust, chip, manifold, filter) go to 200bhp as the whole exhause system ford fit is very restrictive
As to seats on fiesta forums on...
got to be said apart from a minor noise difference i cant tell teh diff between the green filter and std one. i also changed over a couple of weeks changed to pd160 air intake then a week later did the green filter
the handling of the ibiza (at least my tdi sport 130) is dreadfull it just understeers whatever you do (its better with tc off but still bad) and lets be honest the interior is pretty dull. Also in my experience its not that well bolted together
also bear in mind apart from the fiesta and jazz...
from a quick read id say you aint getting enough air or the maf is f*cked
could also be your ecu god forbid lol