I am also looking for some advice on this matter. I have consulted ottersccustoms for answers in the past, but it seems his site is down atm. I will describe my setup as best I can below and hope someone can give me a direction to start towards in reference to finding the right spring combo.I play mostly woods ball, so long range accuracy and a quiet shot are factors.
My gun is as follows :
Mod Bolt - Venturi removed
Mod valve, bottomline and sanded sear pin ala Otter
Bob Long Cyclone reg w/Macroline kit
Custom trigger job of my own creation
Smart Parts progressive barrel
I am currently unsure as to my working PSI, but I will know in a week when my guage arrives. I have no chrono numbers for my gun as it has not been tested for over 3 months and i've been steadily upgrading.
I plan on getting the 32* spring kit which comes with 3 velocity springs and 3 valve springs.
Any advise would be appreciated to help me save some time experimenting to get the gun in peak shape ASAP.