Does the Hammer engine have those vacuum caps on the right of the throttle bodies like the Freedom 92 has I wonder. I would get that sputter before I found one of those vacuum caps cracked. I ask as you said you changed the clutch cable and on the freedom engine those vacuum ports about about 2" away from the routing of my clutch cable (04 TC) right about at the mid cable adjustment point.
You should be able to see up in there without pulling the tank, one on each TB, facing rear, about 1" long above and behind the clutch cable adjustment if in fact the Hammer engine has those ports. I can post a pic of mine to see if it's similar, sorry that I am not familiar with the SC configuration. Im with Crossroads and Vissionjohnny, Vacuum leak. I don't buy into the we can't fix it, sell it at all.
2011 White Vision - Nuvi 550, Lowers, Lloydz 2nd filter, Vic perf filter, CB/Icom, 96 Brake LED's, Clear Signal lens/Switchbacks, VIC Hwy Pegs, Stebel Horn, 7Jurock 15" Shield, PCV, Lloyd ATS and Variable intake, Ness honkers
2004 V92 TC - S1 flash, level 1 slip-on, Ness big sucker K&N, ISO Grips, 4x1.5 Highway Hawg Risers, extra chrome (never too much), JM 2k CB 4' antena, Mustang seat, HD Front TS & Lowers, OD Pulley
Retired Navy SCPO