A street engine. This is where people spend too much time with their noses in hot rod books and buying all the forum gurus BS. A short rod is good for high piston speed and it makes the engine pull more vacuum at low RPM. Generally speaking, that's what you want in a street engine. This is another case of "everybody's doin it, so it must be the thing to do". As I said before, long rods have pros and cons, just as short rods. It boils down to WHAT you're doing. Read this: