Building The Chassis For Project F-Bomb - HotRod.com

Part 1: The Structural and Philosophical Backbone of Our New 1,500hp, Do-It-All, Dare-To-Be-Different '73 Camaro.

Writer: David Freiburger
Photographer: Randy Lorentzen, Planet R photographer

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Every magazine project car's got to survive the harsh scrutiny of the readership. To save you the trouble, we'll plead guilty right up front: Here's yet another Camaro, it's unspeakably expensive, we did virtually none of the work ourselves, and some guys will think we're out of our glue-sniffing gourds for painting it flat Army green. Yet we're counting on winning you over with the F-Bomb, as it absurdly embodies HOT ROD's editorial doctrine by Daring To Be Different both aesthetically and purposefully. We've spoken against overpowered, underperforming, undriveable show rods, so this is our comeback: a true 1,500 hp we hope to drive every day and race on the dragstrip, in top-speed events, and on road courses. This'll be one twin-turbo small-block that's more than just set dressing.

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That's an awful lot of swagger considering the character of the car was a moving target during the early months of the project. Truth is, during the buildup of the Nelson Racing Engines twin-turbo, 406ci small-block that appeared on our Sept. '06 cover, Tom Nelson badgered us relentlessly to lend him a car in which to mock up turbo headers. One morning, he just sent a tow truck, so we handed over a '73 Camaro we'd bought a couple of years earlier for $800. A few weeks later, Nelson called again: "Dude! We stripped all the paint off your bomber. We're gonna paint it and put in the turbo motor!" The project was haphazardly born.

At first, it was going be a straight-up Pro Touring car, probably more Trans-Am-inspired than most. Then it was going to be a stock-appearing street sleeper; that died quickly. For a few weeks, we'd decided on a pure drag car in bright orange. It took a lot of arguing to finally pound all the players into accepting the F-Bomb scheme you see here. Come to think of it, the Bomb has led to lots of infighting and indecision over the past year, so this project series will reveal all the tribulations, the reasons for our decisions, and the stuff we had to redo-sometimes multiple times. There should be lots of tips and tech that can apply to any car, even if you never plan to build a car as excessive as this.

The F-Bomb has a leg up on many magazine projects in that, as we write this, the car is already nearly finished. It debuted at the SEMA show in November 2006 to overwhelmingly positive reviews (and at least two guys who hated it), though it's yet to move under its own power because it's low on wiring and the suspension is far from sorted out. How the Camaro will or won't perform remains speculation, but we hope you'll stick with us over the next several issues as we go through the paint, the trick fabrication, and all the little details required to get the F-Bomb into its phase-one, street-and-strip configuration so we can start to drive it every day like a grocery getter.

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For now, here's step one: the chassis fabrication.

Though we waffled on the details of paint and style, one thing was always in our Camaro's plan: real, hard-core use on the track. The F-Bomb wasn't built for any particular class of racing within any given sanctioning body but was schemed to be legal for a number of activities starting with drag racing and, after reconfiguring the suspension and trans, progressing to land-speed, open-highway, and road-course events. That meant we studied all the rule books and overbuilt the car for every possible contingency.

Even though we thought we had considered everything, the project snowballed once the fabrication began. So we really got to know Nick Miserendino at Red Zone Race Fabrication. Not so much that he was willing to yell at us, but he wanted to many times. We picked Miserendino as our fabricator after seeing the quality of his work on such cars as Pure Vision Design's GTX-R (HRM, July '04) and George Poteet's '68 Charger (HRM, May '06). Red Zone was also recommended by Nelson and some other local fabricators, plus Miserendino was willing to let us dog him with a camera and call a lot of the shots as the car went together. He hated us for a few weeks there at the end, but the teamwork had a big payoff. Miserendino's a perfectionist and a fabrication wizard, but equally important was that he was able to hand us the function and safety we needed while keeping an eye on style. Few things are more hideous than ill-fitting or nonparallel rollcage tubes, but when formed properly, the shape of the 'cage itself contributes heavily to the character of a car. At Red Zone, we spotted road-racing import cars that inspired us to add the punch plates that affix the front rollcage legs to the A-pillars of the car. That one decision set an industrial look that grew into an aircraft theme that meshed perfectly with the fuselage shape of the second-generation F-car. So, while Miserendino's work was for function, his execution wound up defining the theme of the car.

Ah, function. We had big choices there, chiefly related to whether we ever wanted the Bomb to run 7s at the dragstrip. The problem was that NHRA rules for cars quicker than 8.50 in the quarter now require Funny Car-type rollcages that enclose the driver, and we feel that type of 'cage virtually eliminates extended street driving. We compromised by using the 4130 chrome-moly tubing that's required for the quicker 'cage and designing it such that we could add the Funny Car pod and a few other details to bring the Bomb to 7-second specs if so desired in the future. With an estimated 100 feet of tubing in the car, the chrome-moly saved about 20 pounds compared with the thicker wall required with mild-steel tubing. However, while the NHRA only requires 15/8-inch-diameter, 0.083-inch-wall-thickness chrome-moly tubing, the open-road-racing events demand 13/4-inch, 0.090-wall tubing, so we went with the larger size. The open-road-racing and land-speed rules recommend against chrome-moly tube, as it can be brittle near the welds if the area is not flame-annealed to normalize it after welding, but they do not outlaw it.

See the captions for all the other details it took to make the F-Bomb as safe, fast, and cool as possible. This story focuses on the rollcage and chassis fabrication, though Red Zone also installed the all-new Detroit Speed and Engineering minitub kit for second-generation Camaros and Firebirds. Look for those details in the suspension portion of the project coming in a few months. Read more on www.HotRod.com/articles/hrdp-0703-project-f-bomb-chassis-build/

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