Have a 97' 700 with SLP twin pipes, porting and head. Was runninh at 3000-6000ft last year and it ran perfect. Ever since I moved to Utah this year can't seem to get it to run good. Have tried 175-180 mains and 38-48 pilots. The 38 pilot(no boost bottle) and 175(pto)/178(mag) seems to work best. Runs great at 7,000-8,000 ft., but has a lot of sputtering up 9,000-10,000. Was wondering what needles people are running with this set up at 8,000-10,000 ft. SLP says the stock R1370J should work fine (thats what I'm running). Tri-City recommens changing the needle to 1372J. They say this is a little leaner and should help.Any help would be appreciated.