what ph clio??
depends on how low you want to go, what geo set up you opt for (camber settings ect) and what wheels you have.
imo get the coilovers on and set at a height that suits you then get them set up how you want them, then measure the tyre to arch gap, the answer will tell you the max you can fit...
if you go for a factory geo set up then 30mm front and 10mm rear (total track) looks pretty good and still gives decent room for spirited driving.
anything over 5mm NEED to be hubcentric or you will get wheel wobble and get the aluminum ones by fk or eibah or h&r to keep unsprung weight to a minimum...
venom motorspot are pretty competative with prices!!