Just adding my "yep!" to all that has been said. I like to say that all it takes to get cubic horsepower is cubic money. Engine building is not an inexpensive undertaking. Make a plan, do your research, and try to stick to it. Mike has laid out a pretty good synopsis of what you need to consider.

As an example: in 1980, I needed a quick new engine for my daily driver, and didn't want to go through the process of rebuilding my worn out engine, so I bought a crate engine from GM for about $1,200. There was a glitch in it, and GM found that all of the engines in that lot had the same glitch, so rather than wait for a new engine, I took them up on an offer of a new crank, and a rebate if I wanted to handle the swap myself. So, in the process of tearing the new engine down to replace the crank, I decided to go ahead and change the cam, and have the whole thing balanced. In the end, after all of the little things got taken into consideration, I wound up into that engine about $3,500 to $4K, and that was a lot of moolah in 1980; it ain't peanuts in today's figure, either, but it will be real easy to drop two to four times that into a custom build.

Just sayin'. It's easy to dream, but reality bites.