The days of a guy working late into the night assembling a warmed-over engine for his hot rod may not be over, but they're certainly not as common as they once were. With readily available crate engines making horsepower numbers that were once thought of as strictly drag car power, it's easy to see why the shift has moved to boxed powerplants. High-horsepower engines might be the ones that get everyone excited, but just about every company that offers one of those has a mild street version priced right and warranted that would be perfect for any street rod or custom. Here are a few examples and a list of companies that can get you down the road.