I doubt its going to be a massive difference, but ive only driven cars with manual and 16v pas so couldnt say from personal experience! all i know is the 16v pas is great, feels just like manual steerring when you're on the move, you only notice the assistance when parking.
in a pinch tho i wouldnt have a problem fitting an 8v rack if its a known good one

the bracket thats bolted to the pump is:
027 145 521 - 27.72+VAT