[blykins]

Todd, 550 from a SBF is not that big of a deal. You can do it on pump gas, and make it very streetable. Of course you start with a 351W block....a little stroke....maybe to 392 or 408 ci, 10.5:1 compression, AFR or TFS heads, a single plane intake, a good carb, and a good roller cam with roller valvetrain....voila....As a matter of fact, I just ran a desktop dyno for a guy with a stock bore and stroke 351W with 11:1 and TFS heads and a decent cam.....it made 525hp....now 11:1 is a little high on the street, but you could gain that back with a higher stroke rotating assembly. 550 streetable ponies isn't hard.