QUOTE(ttraynor @ Feb 15 2008, 06:49 AM)

Changing the secondary is the ONLY change you made? See, Billy the Hillbilly at Howard's--who is very respected for his clutch kits, is trying to sell me a stiffer PRIMARY (from a stage 1 kit, I believe) as the solution....Very confusing. Cudneys does make a dedicated 600 SDI kit, then there is the Doo Talk thread saying not too good results across the board from that kit.
Thanks
The dealer DID put an entire new primary on, but in my case is did not work. We did the Primary, then the fuel system, then ECM and EGT sensor (Together) and finally the secondary spring. They did each of these changes one by one (with the exception of the ECM and EGT sensor, which were done at the same time.) and I tried each change for a couple days. Nothing changes until we swapper the primary. Like I said, my top end dropped to about 93mph, so you lose some on top, but you gain a ton on the bottom end.