I like the big blocks. Is this question on stock engines or modified? On the street a small block a body might get you light to light, but on the hwy, the big block would take charge. You need to wind up a small block when they were stock to get anything out of them. Plus taller gears to get the rpm's up. So they wore out quick. A big block just thumps and goes. The whole game changes when modifications start to fall into the scene. The one with the most money and training usually will win whether bb or sb. So with todays parts, anything can be made to go and be light. You can build a 540 bb and weigh less than a small block now. And you can make feather weight small blocks as well.