Front suspension question

[leon205gti]

Hi there, I´ve converted my ae86 kouki front legs to coilovers using a DIY kit, that works with 2,5" springs. The inserts are bilstein.

My empty pockets and the afraid to order the wrong size and rate let me use a peugeot 307 rear springs (its too soft) until I get the good ones.

Im using 15" and the car is dropped a bit. It has about 3cm between tire and wing. Its a dayly drive car and sometimes i take it to track and to drift it as well.

So what size (long) and spring rate shound I order? I also have helper springs seats (not used at the moment) should i get them too? which size?

Many Thanks in advance

Cheers