Out of those two engines, definetly go with a KA24DE. Its a great engine. Strong, and reliable. idk anything about the other engine. but the KA, in N/A form will make upwards of 220-240rhwp on motor w/o juice. With a turbo, you can manage 350rhwp on stock block, so anywhere from 10-12psi, maybe even 14psi on a T3/T4. The only problem with the KA is the weak ringland. They will blow after 1bar (14-15psi). If you run forged pistons ( many choices, Supertech, Weisco, Ross,) Forged Rods ( Aries handle up to 700rhwp), you should be able to make around 500-600rhwp with 25-30psi on a big turbo. You can run a T66 a SC61 a T3/T4Oe. The head, stock flows pretty well. On N/A cams you can make decent power, If your cheap, swap in a altima's intake cam so you'll get 248/248. Anyways, if your going with a 4 cyl, definetly go with a KA24. If your going for a high revving car, get a 3rotor, 13B, plenty fast with a turbo. Also, dont get a S2000 motor because it would take a shitload of money to make it fast, if you put I/H/E you could actually lose power on it.