Even though the civic si has a k20 I heard that it was overall not as good of an engine as in the type s rsx. That was the main reason that when I got my si I went with the ek rather than an ep3. Tho an ep3 with a jdm k20 or the type s motor would be pretty sick. Either way though it is a honda, so you know you'd end up with an engine that will last a long time and has tons of potential.