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I have a sc400 1uz w/ vortech v2 si with a 3.08" pulley and its running 6 psi @ 6200 rpm intercooled. Tuned and dyno'd @ 275 whp in 100 degree vegas weather. Just want to get it over or at 300whp. My question is how much do i have to drop in size on the pulley to get another 2 psi? Anyone have any experience with this?

plus i cant have my free 85 sr5 pickup i put a 1uz in be faster than my lexus cause it sure feels and seems that way lol