I am looking to do some upgrades soon (all mods in my sig). Now i don't have the extra cash for springs and retainers at this time for the S2's. So what i want to know is if i should just do the S1's or go with the S2's and change the springs next summer when a send out the IX turbo out to FP for a green? Also i have no intension of spinning the motor past 7,500.