Dave Wilcox, driver of Scott...
Dave Wilcox, driver of Scott and Joe Roberts' Dirty Bird says, "When it comes to the burnouts, I'm just having fun. I should keep the rpm low and not go too long, but I put it in high gear and go. The crowd loves a show, so I give them one."
You may have noticed at Pontiac events over the past several years, that a few racers and engine builders have made it their quest to build the fastest Pontiac ever. Competition to field one, be it a funny car or a dragster, has steadily heated up and the latest effort to reap positive results is Joe and Scott Roberts' Drag'N Rac'N funny car, named Dirty Bird. As of press time, this machine has run a best e.t. of 6.527 seconds at 213.16 mph with driver Dave Wilcox at the controls.
Scott's relationship with Pontiacs and speed has a storied past. His first car was a '68 Firebird that incited his addiction. With the assistance of his father, Joe, he began to restore and modify it. "Every time we pushed it further and were pretty happy with it, someone would say it could go faster. It was never ending," Joe recalls.
After a smoky half-track burnout,...
After a smoky half-track burnout, Dave flips the top open to get the smoke out, shifts into reverse, and backs up straight. Once near the tree, one crewmember behind communicates with another in front to line the car up in the groove.
This mentality was just the sort of off-kilter thinking that was necessary to take the next step. "Let's build a Pontiac that will be faster than anything else," Scott proposed. This statement got the ball rolling on an extraordinary project that would go to the heart and soul of Pontiac performance.
A group of open minds was assembled to get the adventure started. Family friend Dave Wilcox of Dave's Horsepower Shop signed onto the project, to turn wrenches and to drive. (Being NHRA licensed to run 6.00 has its perks.) Jim Lehart, owner of Central Virginia Machine Service in Burkeville, also offered his engine-building skills free of charge. Frank Gostyla and Bob Cacciotti at AllPontiac.com came aboard, as well.
"One thing that I knew out of the gate was that we were going to use a funny car," explains Scott. "As strange as it sounds, it was just cheaper to build a funny car than a door slammer." After the team had considered, but ruled out an older funny-car chassis, Scott's friend Phillip Hooper offered to sell the Roberts a 125-inch-wheelbase '02 S&W chassis that only had a few runs on it. They bought it rolling with a body-a Camaro body.
Back behind the starting line,...
Back behind the starting line, the top gets closed and Dave creeps up slowly to let the crew wipe the tires off. Then he stages. "I'll stage shallow if I'm going for a good e.t.," he says. The transbrake is set for 3,500 rpm, and the converter flashes to about 5,600 on launch. Short times run in the 0.980s on a good track with good tires.
After the chassis was chosen, Scott got into the details with Jim and Dave to begin building the ferocious Pontiac engine. The starting point was the IA II block from AllPontiac.com,the attributes of which you just read about in the twin-turbo engine-build story in the last issue. It's plenty strong enough to produce the power to reach their goal reliably. Jim performed all the necessary machine work, and Lewis Robertson of "The Shop" in Charles City, Virginia, sleeved the lifter bores.
Dave ported a pair of AllPontiac.com Tiger heads to flow 450-plus cfm and they are held down by ARP fasteners. There wasn't an intake manifold available that would mate a 14-71 blower to the Tiger heads, so Dave made a custom piece. AllPontiac.com developed a front bearing support for the crankshaft. "The caged bearing helps to offset the thrust of the blower pulling the crankshaft up," Jim says.
Dave contemplates another...
Dave contemplates another 6-second pass motivated by the 475ci IA II engine fitted with Enderle mechanical fuel injection, a Littlefield 14-71 blower, Tiger heads, a secret-spec solid-roller Comp cam, and roughly 1,900 hp.
The development didn't end there; Frank plumbed a Pfluger dry-sump oil system after the original plan for a Titan Oil pump wouldn't work. An AllPontiac.com oil pan and a Canton windage tray round out the oiling system.
Filling the IA II block are Ross 4.350-bore forged pistons, connected to Brooks B-4 Nitro 6.800-inch aluminum rods, and a Scat Billet crankshaft with 3.00-inch mains and a 4.00-inch stroke. The camshaft is a custom, solid roller "4-7 swap" with 0.850-inch lift from Comp Cams-lifters and pushrods are from the same company. That's all they will divulge on the cam. Jesel shaft-mounted roller rockers with 1.9:1 intake and 1.8:1 exhaust ratios actuate Tiger/Manley 2.250/1.750-inch valves.
The 475ci Pontiac feeds on methanol, delivered by way of an Enderle fuel pump and mechanical fuel injection system through intake manifold port-mounted nozzles. Air is ingested through the Buzzard Catcher intake butterflies and into a Littlefield 14-71 High Helix supercharger with a 40 percent overdrive. The compression ratio is 10:1.