the L6 in stock form in the lightweight s30 body is not a slow car, tons of fun, but with time your gonna want more, I assume thats where you are now, modifying theL6 can get some nice numners wether stroking, or a F54 flattop with high comp head, or a bumpy cam, lots of ways to go makes it faster and more fun, as time passes your gonna want more, hopefully by then you'll have gotten some good experience under your belt, and will be able to evaluate the best next step for you, I just think your better off taking it slow instead of buiilding a 4-500 hp monster right away, you'll also likely decide to modify your suspension and brakes along the way, and your less likely to get discouraged by taking on a job that might seem like too much half way through, we all want you to suceed in making your car into what you want, we'd all hate to see another person bite off too much at once, get discouraged and walk away, possible for good, take it slow, learn along the way and you'll be better for it, without having to learn it all at once