by Tommy Lee Byrd
(Excerpt from Street sleepers : the art of the deceptively fast car published in 2011)
When you have 1,200 hp at the mercy of your right foot, it’s not difficult to obliterate a pair of rear tires in an afternoon of spirited driving. This car has run a best elapsed time of 8.92 at 162 mph through the quarter-mile. Rob also competes in standing mile top-speed events, where the car has trapped more than 215 mph! (Photo courtesy Rich Chenet)
Rob bought the car for $900 a few years ago and built it into one of the best sleepers on the planet, with the help of Tom Napierkowski. The duo tackled every detail with intentions of making this a very sneaky car, and never really planned to participate in organized racing with it. When it was first built, the car didn’t have a roll cage or any safety equipment, and that’s when it was its sleepiest—it currently has a few more safety details, but the photos you see here are from 2007 to show off the car’s true potential as a sleeper.
The car is rough and ragged on the outside, bearing its original paint, which has certainly seen better days. It’s not perfectly manicured, or precise on the outside, but everything changes when you look beneath it or check out the engine bay.
Originally, these Pontiac Tempests had a transaxle rear end that severely limited their potential as a performance car. Most folks, including Rob, ditch the original setup for a solid rear—a 1957 Olds for this particular car. The big rear end is narrowed 3/4-inch on each side and features a pair of 35-spline axles, but still utilizes the original 3.08:1 gear set. It’s strong enough to hold up to the big-block’s torque, and the rear suspension works flawlessly on prepped surfaces, as well as unprepped pavement. It’s a custom ladder bar design, with 175-pound-per-inch springs and double adjustable race shocks. The only modification to the front suspension is a pair of QA1 shocks.
Supporting all this horsepower is a mighty Oldsmobile rear end packed with 3.08:1 gears and 35-spline axles. Ladder bars and coil springs help put the power to the ground, while shaving 3/4-inch from each side of the housing allowed for the 28x11.50-15 street slicks. See anything unusual in this photograph? (Photo courtesy Rich Chenet)
Power comes from a 496-ci big-block Chevy, which started life as a basic 454. The big-block features an Ohio billet crankshaft, Oliver 6.385-inch connecting rods, and a set of custom Mahle forged pistons, so it’s safe to assume the bottom end is plenty strong. Atop the short block is a set of Brodix Big Brodie cylinder heads, ported by Rob and installed over a set of Fel-Pro MLS head gaskets to create a compression ratio of 8.6:1. Massive Ferrea valves are put into motion by a Bullet camshaft, which is designed specifically for lots of boost. The intake manifold is a Holley Strip Dominator, which has been modified to accept the modern fuel injectors (Bosch 160-pound), and to match the ports on the Brodix cylinder heads.
Under the hood, you see an engine coated in Pontiac Blue paint, and fit with an original-style air cleaner for a 326-ci Pontiac engine. What you may not notice is the big-block Chevy that hides under the Pontiac hue, and the small pipe that connects the air cleaner to the firewall. (Photo courtesy Rich Chenet)
Fuel delivery is controlled by an Aeromotive A1000 pump, which draws racing fuel from a 20-gallon aluminum cell. Ignition is controlled by an MSD 7AL box that sends fire to the MSD low-profile Pro-Billet distributor.
Mike Doban of OST Dyno tuned the car on the dyno, using the F.A.S.T. XFI system, and it put down 1,247 hp at the rear wheels. That’s more than 1,500 at the flywheel, and it looks bone stock!
Obviously, Rob had to put a serious transmission behind the big-block, but he didn’t go for the obvious Powerglide. He installed a TMC-built TH400 transmission, which is a 3-speed automatic. The bulletproof transmission has lots of billet goodies inside, and a TMC electric valve body, which also features a trans brake. The torque converter is a Neal Chance 10-inch unit, which stalls to 3,800 at the line—plenty of RPM for the turbochargers to begin spooling up. Traction comes from street-legal tires, and Rob has switched back and forth between a pair of 325/50R15 Mickey Thompson Drag Radials and a pair of 28x11.50-15 Hoosier Quick Time Pro DOT cheater slicks. These are mounted to a pair of 15x10-inch steel wheels from Stockton Wheel. Stock poverty caps top off the beater look.
The end result of Rob’s work is a killer Pontiac that surprises everyone in its path. Whether it’s at the drag strip or on an abandoned airstrip making a top speed run, this Pontiac seemingly does the impossible—go fast! It looks like a beater, but has proven to be quite the performer despite its poor aerodynamics. Rob has run a best of 5.85 at 130 mph in the eighth-mile, and a best of 8.92 at 162 mph in the quarter—and don’t forget about a top speed of 215 mph. Rob has proven the potency of his Pontiac numerous times, and with quick elapsed times and mind-blowing top speeds, no one can deny this car’s ultimate sleeper status.