how low can i go?

[Clio Madness]

i current have a mk2 clio 1.2 lowered 40mm on 17s, i would like it lower, ive saved some money and want to buy some smaller wheels and prob some vmaxx coilovers, but i want to know how low i can go on 15s and 16s on vmaxx coilovers without scrapping atall.

any help?

thanks
:S