Well in the USA we dont have Civic IS or wait you mean Si yes never came in the us unless the 1992-1995 SOHC vtec 125HP D16Z6 or the 1988-1991 SOHC D16a6 non vtec, but hmm RSX is nice but weighs to much and K-parts cost alot, Integra GSR or Type R well the Type R is hella better but in the USA its going get stolen I say Civic drop the RSX motor and you have a low 13's street car k20a.org