N/A motors are clean. But like Eviloliv3 said the majority or N/A engines put down just under 300 whp. Now you can do an all motor set up and push that much, but if its not enough, you can throw a supercharger on it and then if you need more give it a nice shot of nitrous. But before you build your motor decide whether you want turbo or all motor. I have a GSR and I have been back a forth for months on which way I want to go and I still haven't decided. But whatever you do, I'm sure you'll have fun.
Oh yeah, the GSR is a 1.8L engine (about 1797cc) although you can bore it out and make it really close to a 2.0 which is bad ass.
Yeah out of non-vtec like Eviloliv said, FI. Now you said you're looking for all motor but if you want FI but not all the maintenance, supercharge your car. I'm not guaranteeing your engine will hit 300HP but for what your looking for from my point of view, I'd supercharge your car. Turbo's are way cool and all and give mad power, but there's more maintenance than a supercharger. You could look at a supercharger like a Cold Air Intake on steroids. Nitrous is also cool, you could run a 100 shot and be good.