F20B!!! It is virtually the same engine as the jdm H22A type S with steel sleeves, slightly smaller pistons and a shorter stroke. Short stroke=high RPM's. The stroke is 88mm, which is shorter than the B20 as well. It is almost as short as the B18C5, which is 87.2. I say get a F20B, get it sleeved if you want, and use 87mm H22A sized pistons instead of the stock size 85mm, and you will have an engine that has a higher displacement than the B20 (should be about 2050cc's, or roughly 2.1L), but a shorter stroke. It should have no problem turning 9k+ RPM.