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1967 Chevy Camaro - Two Turbos, - No Waiting

David Welker's 8-Second, 150-Mph Camaro With Attitude

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It's 1:30 a.m. and we're mere blocks from home when a local cop yanks a U-turn and comes blasting after the bright yellow '67 Camaro. We idle through neighborhood side streets with the cop following, lights flashing and the spotlight drilled into the interior. All we need now is the local news chopper to make this a real media circus. "I'm not stoppin' til I get home," David Welker says, and it's clear he means it. But it's not about running. "I don't want anything to happen to the car." It sounds like the voice of experience. We pull into David's driveway and it turns out the cop used to live in the same neighborhood and knows David. There's no harm, no foul, and best of all, no ticket-this time.

While the cop didn't recognize the car, every other street rat in the greater Phoenix area certainly does. The kamikaze bikers who made an entrance at the Sonic burger earlier that evening talked big but didn't want to race when they saw the parachute on the back of the Camaro. Oddly, they missed the two turbos peeking out from under the fiberglass hood. The bike dudes got off easy.

What's impressive isn't that this is an 8-second street car. That game is becoming more familiar every day. But most times, that performance comes with a high-tech price tag-expensive turbos, an incomprehensible EFI package, and lots of custom-fabbed plumbing. So what makes the naysayers a bit flustered is when David and his son James (he calls himself RJ) pop the hood and a lone carburetor sits atop a single-plane intake manifold.

The Camaro started out as a father-son project. James wanted to take on the 1,320, so David bought the old Super Street racer from his friend Billy Carroll. Carburetors and turbos have always been the combination, with the first attempt to hide them down low stuffed behind the headlights in a twin-carb draw-through configuration. "They said it wouldn't even start," David says. "It ended up running a best of 9.30." The problem wasn't power, but rather a struggle to pump oil away from the turbos. "We tried all kinds of stuff, but the engine would always blow smoke when we first started it up. Carburetor cleaner is your best friend when you work with pull-through turbos." There were other, equally vexing problems as well. In a draw-through system, the intake manifold and the long runners leading up to the manifold are full of air and fuel. If (or more appropriately, when) the motor sneezes, all that fuel and air contribute to a big bang.

The next step in the learning curve was to dump the massive 211/44-inch-primary-pipe headers and trim them down to much more conservative 131/44-inch primary pipes to put more energy into the turbos. Combined with a pair of budget 58mm TO4B turbos from Joel Britt at Arizona Turbo, the package began to take shape with new homebuilt headers that positioned the turbos up high and right through the hood. According to David, "They're just $250-apiece industrial turbos. They're not ball bearings and they aren't ceramic. They're not even off-center turbos. They're old school, but they work."

David also hits it with a 150hp plate shot of nitrous on the starting line. "We use the nitrous to spool up the turbos, but we've also used it down track." While this might seem like wretched excess, David's plan is actually quite sane: "We use the nitrous to help cool the incoming charge." The nitrous comes out of the plate at something like -65 degrees F, which does wonders for turbo discharge temperatures that easily see the high side of 200 degrees F.

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