I love the SR20DET in mine, but it is a very tight fit and more power than you'll know what to do with. I prefer lightly built turbo over fully built NA 100% of the time. Not that the KA24 is a bad engine, SR20s can be very temperamental, but if you just do light mods and treat them right they're solid for 300 rwhp and 30-35 mpgs in a B110. The SR is pretty lightweight too. I'm not sure how they stack up against each other weight-wise, but aluminum block, ditch the A/C, PS, and every other not needed accessory and it'll probably weigh the same or less as an NA KA24 (since you have to add an intercooler, turbo piping, BOV, etc). The great thing about an SR20 is if you get tired of 200 rwhp (stock redtop), you can just turn up the boost and retune to ~240 rwhp, and when you get sick of that you can swap turbos and injectors and retune to 350-400 rwhp pretty easy/reliably. The NA fully built KA24 is pretty stuck where it's at power-wise unless you turbo or nitrous it.