Not to get too side tracked - but I see Summit sells a 430 horsepower streetable 383 roller SBC ffrom Blue Print Engines for about $4,600 with a 30 month, 50,000 mile warranty. I've seen a few of the Blue Print engines and the car owners speak well of them. I don't think you could build one for that amount by the time you hunted down a good core and had all the machine work done plus sourcing all the parts, cast steel crank stroker crank, good heads, etc., not to mention the time required to properly assemble.

However, to find 600 horsepower in a SBC (without nitrious) you need to look to someone line United Racing. They have a 603 horsepower 406 stroker built on a Dart block with a 3 Year 100,000 mile warranty for a cool $12K...

Yup - tis expensive to build big horsepower from a small block.