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.

Dyno Results Superflow 902 Dyno STP Correction Factor Tested At Westech

RPM TQ HP
3,600 685 469
3,800 707 511
4,000 734 559
4,200 750 600
4,400 756 633
4,600 755 662
4,800 752 687
RPM TQ HP
5,000 741 706
5,200 727 720
5,400 712 732
5,600 691 737
5,800 669 738
6,000 642 733

SOURCE
Accufab Inc. (John Mehovitz) Edelbrock Corporation
2700 California St.
Torrance
CA  90503
310-782-2222
www.edelbrock.com
Automotive Racing Products (ARP)
531 Spectrum Circle
Oxnard
CA  93030
805-278-7223
Fuel Air Spark Technology
151 Industrial Dr.
Ashland
MS  38603
662-224-3495
www.fuelairspark.com
Autotronic Controls/MSD
1490 Henry Brennan Dr.
El Paso
TX  79936
915-857-5200
Lee Performance Products
Butler Performance Group
2336 Highway 43 S, Dept. HPP
Leoma
TN  38468
Moldex Industries
BOP ENGINEERING
N3651 Schmidt Rd., Dept. HPP
Jefferson
WI  53549-9768
Pure Pontiac (Andy Mitchell)
Canton Racing Products
232 Branford Road, Dept. MMFF
North Branford
CT  06471
T&D Machine Products
Carson City
NV
7-75/-884-2292
www.tdmach.com
Competition Cams
Memphis
TN
8-00/-999-0853
compcams.com
Wenzler
Crower Cams & Equipment
3333 Main St.
Chula Vista
CA  91911-5899
619-422-1191