id say you could def run 12 psi no problem ,i think jj ran 15 for 55k or so allen told me on stock lower end and tune.i run 15 all day and beat the snot out of mine .although for tranny reasons lol i did just reduce to 10 psi,till i get my built tranny back in.run meth get the right tune make sure youre a/f is on the money ,run soome 93 octane ,,and if its worth all that do it.if not run SAFE at 7-9 psi and wonder all day what else you can spend money on ,innstead of changing the pulley.these cranks have been proven too hold 600 hp all day. youlle get THE BUG if you keep reading this forum.lol my 2 cents
mods:2004 sierra ext sb,20s ,big brake kit w,hawk pads,air bagged,2006 6.0 lq4 swap,vortec supercharged10psi, air to water intercooled w/ dual electric fans on it ,snow meth injection kit,60lbers, e-fans ,big radiator swap ,cam 218 /222 548/550 comp .hardened prs .1.85 comp roller rockers ,guideplates ,crane double springs,trans 4l65e built .pacesetter l/ts true duals w/x pipe and magnaflows,14 bolt rearend swap ,3.73s,aroemotive fuel pump system w/elec.fuel controller and bypass regulator a/n fittings, taylor 10.5s interceptor gauge,aem w/b a/f ,autometer boost/vac NELSON 93 OCTANE TUNED .