go ITG Maxogen - from everything i have read on here they are the best ones for the clio. Decats are fantastic, had one on my clio but havent got round to putting it back on, made huge difference in driveability. I have a full system which helped a bit, and then a chip to make sure your getting the best from it all. My full exhaust including decat cost £390, though for an extra £50 and some petrol you could get a full system from Hayward and scott - if the group buy is still going - for £440 and they are meant to be fantastic. Id say with all that youd get 10bhp, but if you got a better mainfold (182 manifold) youd probably get 15+ bhp
[Edited by theduckeatspork on 23 July 2005 at 11:15pm]
This is where someone that knows more than me - mailto:andy@gdi">andy@gdi or benr from angelworks will correct me for those figures being over the top.