December 2003 Alpine Honda Civic Si

At this point in our 2003 Alpine Honda Civic Si buildup, we're pretty much done with the front of the car. The center drive, seat and dash areas are complete and ready for the primer/paint process, so it's time to start on the amplifier area at the rear. We really wanted to do something different with this area, and the center drive gave us a lot of space on each side of the seat to do something cool. We also needed some place to mount our Civic's gauges, since the dash area was completely taken up with monitors. We thought it would be unique to mount the gauges in protruding arms that reach around each side of the seat, connected to the amprack in the back. Here's the problem: how do you get into the car with the arms wrapping around the seat? The answer was to motorize the entire structure back three feet to allow access to the seat.

The first step in building the rack was to make a sturdy base for it. Since the rack had to slide back and forth, we found some industrial-strength forged steel slide racks designed for moving CNC machines back and forth with great precision. These racks are amazing, since each bearing cap can handle 10,000 pounds of load capacity! That means that with the four caps we used, we could support 40,000 pounds of weight. Obviously, the strength of the car's unibody is the limiting factor here. With the sliders bolted into the car, we built a steel frame on top of them that the fiberglass rack layers would bolt to. Then, we added the final touch, a 12-volt linear actuator with 750 pounds of load capacity to allow the rack to move back and forth. Now the mechanical structure for the rack was complete, so it was time to build the rest of it.

Our concept for the rack was to have three layers, each one holding an amplifier in the back and Auto Meter gauges in the front. Each layer was built separately by creating an MDF frame along with ABS plastic attached by super glue. These layers were bolted together by installing aluminum plates between each one. The frames allow the amplifiers to be mounted in the back of the rack, and gauges to fit into the front.

Once the layers were framed, they were removed from the car so they could be fiberglassed. Grille cloth was stretched over each one, then the cloth was coated with fiberglass resin. After that was cured, each rack was reinforced with five layers of 3/4-ounce fiberglass mat, making them very strong. Since they are fairly long and thin, strength was very important to make sure they didn't flex or rattle when installed in the car. Dura-glass filled the initial imperfections in the panels, then that was ground down and followed by a thin layer of Rage Gold filler to smooth the surface out.

There were many small details to take care of with these pieces as well. We molded the actual heatsink fins of each amp precisely to match our panels, creating a very clean, flush look. The fitting of each layer to the other also took some time, as did the building of the ABS plastic-bottom panel to hide the steel structure below. With all of these steps completed, the racks were bolted back into the car to check the fitment of every detail. When everything checked out, the racks were ready for the primer/paint process.

That's it for this month, but check out SteveBrownUniversity.com for some unique hands-on opportunities with these procedures, and e-mail questions to sbrown@alpine-usa.com.