Always wondered this.  I fitted one of these to my octy http://www.forgemotorsport.co.uk/images/products/FMDV008.jpg

Great quality dv.  But what in the hell are the 3 small silver plates for?  I have them sitting in the box right now and I've always wondered what purpose they serve??

 

Samuel

I'm sure each "shim" plate is 1-2psi. For that extra fine tuneing

Yeah they tighten the spring a smidge

tighter spring for more boost... it's for if your car is inbetween two springs so one spring would be too stiff but the other isn't holding boost so add 1-3 shims too the weaker spring to stiffen it