900 hp is always achievable. Then again, having Angelina Jolie greeting you at the door when you come home is too (somebody know how that's done?) you don't need to go that high in HP. Stick with what works. A set of 180 or 200 cfm heads with right combo cam will spin 9 grand. Question is, How will the rest of the engine take it? Will your accessories take it on a street motor? And are you willing to keep the bucket of cash at the ready to feed it on a constant basis if you are going to drive it daily or even a few times a week? Start from basics. Good bottom end good geometry (ALWAYS good geometry) ANd use common sense and you'd be surprised how much you can get out of it. Thanks.