how many shims should i be running on a rfl BOV running like 13-14psi ?? i have 3 in rite now does that sound rite?? more boost = more shims or the other way around?? also were is a better spot to mount it, upper or lower IC line?? its in the upper now about 7-8" before the airbox, but ive read were guys like putting it in the lower whats the diff running it there??