1975 Chevy Laguna - The "X" Factor

The Dr. Gas Boom Tube mufflers come squared off, and you'll need to make a decision where you want to cut them, and at what angle. Here it helps to have one or two extra pairs of eyes to check the appearance from a distance. The two major factors we considered were achieving the right angle (parallel to the body), and keeping the end close enough to the car to look cool while not allowing fumes to get inside the cabin.

Now the fun part! Cutting the Boom Tube muffler to your chosen length and angle. Have your work secured solidly, wear eyewear, and take your time. Cut it crooked and you'll have to live with the looks for a long time-or start over. At the edge of the photo, you can see one of the spin traps that are welded in the interior of the muffler. These are the only thing attenuating the noise of this otherwise open exhaust system.

This shot of the oval expansion tube (after being welded to the muffler) shows a couple of things. The angle of the transition may not always be straight out of the cross-pipe, and here it's being trimmed on one side with the cut-off wheel. You can also see how all that work hammering the oval transition into a more square shape has paid off with a stronger, better-looking TIG weld.

Coming in the home stretch, the Boom Tubes and expansion transition pipes have been welded to each other. Also, the Boom Tube and transition on the driver side has been duplicated (length and angle) to match the passenger side, which was done first. At this point, Lang is making some MIG tack welds to establish the final position. This will allow you to do a walk around to check the height, length, and angle of everything. Some tweaking can still be done at this point, and tack welds can be broken if things aren't perfect.

At this same stage, we searched for, and found, some convenient pre-existing holes in the frame where we could mount the exhaust hangers. This should be done only after you have established the position and angle of the Boom Tubes.

Once we were happy with where everything lined up and the tack welds were completed, we removed the mocked-up exhaust, and Lang completed the remaining TIG welds on the bench. By now, the entire system was becoming pretty unwieldy. On the positive side, it's now a solid unit, that can be easily removed and reinstalled should the need arise.

The finished exhaust system before being installed on Project Talladega. It looked like a work of art that would be suitable for hanging on the wall. Shortly after this, we tagged the whole system with a can of high-temp aluminum exhaust paint we had lying around, then bolted it to the car for good.

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