Rat Roundup

This is serious stuff. Sure, small-blocks make great power for their size, but that’s like saying “almost” is good enough. It just doesn’t cut it. If you’re looking for real power, then get serious with a Rat motor. We’re not talking about a 396 or even a 427. If you’re gonna step up to a Rat, make it at least a 454 or a 468. Better yet, throw a quarter-inch arm in a 454 and build a 496. Or you could just let those other guys seem conservative and build a nasty 540. That’s what the big dogs are doing. Don’t let the displacement-envy crowd fool you—on the street or the strip, size matters.

Now that we’ve thrown down the gauntlet, let’s step up and talk about some real power. We’re going to outline a selection of powerful big-block combinations that should point you in the right direction. Our sanctified guide for this big-block power tour is none other than Flowmaster’s own dyno guru and NHRA Super Gas racer Kevin McClelland. Over the years, he has tweaked several powerful big-blocks, and he was kind enough to pull up several examples of righteous Rats that have run across the Flowmaster dyno.

We’ll start with a mild, oval-port big-block torque package for those looking for outstanding grunt in the under-4,000-rpm range, but we’ll concentrate on several big-block combos intended to excel down the quarter-mile. These are not daily-driver packages, but rather the big-cam monsters that come out only at night to prowl the streets. Pretenders beware, it’s a jungle out there and the king is generally a Rat with a big arm.