Butler Performance Group 601-Inch Street Pontiac Engine - Super-Sized!

Size counts. Don't believe us? We'll take the opportunity to try and prove it with this 601-inch street Pontiac. Yes, that's right, a 601-inch Pontiac. A level that until recently has been impossible from this notable breed of engine. Production Pontiacs topped out at 455 cool cubes, and that was ample in the day, but today's aftermarket has made engines of 500-cubes and larger relatively routine. The key components are built into the bottom end, with the foundation being the block. Here, the magic ingredient comes in the form of the Indian Adventures "Tall Deck" block, a burly chunk that can contain the components to build those cubes, and live to tell about it.

The Pontiac experts at Butler Performance Group sought to take advantage of the tremendous potential of this block, and learned that it would accept an enormous 5.000-inch stroke crankshaft with no clearance machining necessary. With a 4.375-inch bore size, a monstrous 601 cubes of displacement could be created. Our interest was sufficiently captured to set out and have one of these behemoths built and tested. Follow along as we investigate this outrageous offering, and know that if Pontiacs are your thing, the experts at Butler Performance Group have engineered a terrific combination of durability and power beyond your wildest displacement dreams.

This particular engine was being built primarily for outrageous street duty on a diet of ordinary pump gas, so a mild compression ratio of 9.7:1 was specified. Displacement of this magnitude is a sure path to absurd torque, so there was no need to build the engine for outlandish rpm. We considered a 6,000 rpm power curve to be sufficient running room, enough to let the torque build to very high power outputs, while producing a combination that will be easy on the internal assembly and valvetrain. Abnormally large displacement is the key here, providing staggering output without requiring destructive rpm levels.

Butler Performance assembled the complete short-block, and also prepared the cylinder heads for the beast. To provide airflow sufficient to feed 600 ci of displacement, Butler opted for their heavily modified "Wide Port" version of the popular Edelbrock Pontiac castings. These cylinder heads proved right on target for our intended operating range. In keeping with our desire for a touch of modern technology married with traditional style, the induction for our engine included an exotic blend of components, though a more conventional induction would likely produce similar results. Our engine proved to be civilized enough for street use, but with savage torque and displacement at work, the competition had better circle their wagons.

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