For the wheels, Buwalda chose Volk Racing GT-U 18x9 and 18x10-inch wheels, and wrapped them in Falken RT-615 rubber sized at 235/40 in the front and huge 275/35 out back. The brakes are from a 300ZX Turbo and were powder coated red to flow with the accent color scheme of the car. Goodridge braided lines, SSBC slotted and drilled rotors and Hawk pads round out the stopping hardware.
Work on the interior of the Nissan started with the filling of more than 800 holes in the chassis to ensure a perfectly flat and seamless foundation. Portions of the floor and firewall were removed or modified to allow for the eventual installation of the mid-bass speakers in the kick panel area. These areas were reinforced with enclosures welded together from 10mm thick hot rolled steel. Likewise, the area under the seats was removed and replaced with 6mm thick stainless steel to provide a solid a foundation for the seats. Once all the body work was done, the entire interior was treated to a chemically catalyzed truck bed coating that provides a hard rubber surface. On top of that, Buwalda applied one layer of B-Quiet sound deadening to the entire interior. The floor also received a layer of lead septum core shielding to further reduce vibration that could potentially alter how the listener would perceive the speaker locations.
The afore-mentioned kick panel speaker locations are now home to a set of 8.85-inch Hybrid Audio Technologies Legatia L8SE drivers. The drivers are mounted to birch baffles that were positioned using lasers. The enclosure behind the drivers can breathe through a grill into the fender area, presenting an infinite baffle installation. The mounting baffle is almost two inches thick and non-hardening clay was used extensively to further reduce panel vibration in the enclosures and the surrounding area, including in the doors. Buwalda is the President and founder of Hybrid Audio Technologies, and with his own company at his disposal, he hand-matched the drivers after burning them in to ensure both sides of the vehicle would sound identical. IXOS 11-gauge Gamma Geometry speaker wire, protected in color-coded expandable tubing was attached to each speaker with 4% silver-content solder. Surprisingly, the installation of the mid-bass drivers was not complete. Waveguides were constructed to direct the output of the speakers toward the listeners and to provide a way to highlight the speakers cosmetically. The kick panel trim in which the guides reside runs the entire length of the door and were wrapped in unprocessed horse leather. Grills were fabricated from expandable mesh sandwiched between MDF panels.
Next in the audio system installation, were the mid-range and tweeters in the front stage. At the extreme outside corners of the interior, where the windshield wiper cowl and the unibody chassis meet is where an additional set of Baltic Birch mounting panels was created. The panels were placed and aimed through an extensive trial and error process that was complimented with in-car acoustics modelling. Behind the baffles, cabinets were roughed in using a mixture of fibreglass resin and body filler. The mixture was poured liberally into the cavity to seal it off from the mid-bass enclosures. Like the mid-bass installation, infinite baffle vents with extruded metal grills were installed on top of the cowl and remain visible from the engine compartment. Stainless steel teardrop shaped panels were fabricated in order to align the output of the midrange and the tweeter in what is called a “zero delay plane.” This means that the sound from both arrives at your ear at exactly the same time. Again, hand-matched post burn-in Legatia L4SE midrange drivers and Legatia L1 Pro R2 tweeters were selected. Both are wired with equal lengths of 11-gauge IXOS speaker cable.
The midrange and tweeters are hidden under an acoustically transparent grill that covers the entire top portion of the dash. The grill was fabricated from 15mm square tube stock. The underside of the dash wears a similar grill, but is covered in acoustically absorptive material to separate the output of the mid-bass driver from that of the midrange and tweeter. The remainder of the dash, firewall and mounting surfaces were treated with foam acoustical treatment to limit sound reflection.
Under the upper dash grill is also where the systems sole subwoofer resides. Before the subwoofer could be mounted, extensive work was done to the firewall and a stainless steel welded notch was created. With the prep work done, a custom-assembled 12-inch Fi Car Audio subwoofer was mounted in the very center of the dash. A cylindrical enclosure was fabricated out of Baltic Birch, fibreglass and chop mat. It extends down to the transmission tunnel where it is vented to the exterior via a 5 x 9 inch opening.
The stock crash bar served as the foundation for the custom dashboard. MDF and aluminum flat stock was used to create the new dash, and it was covered in matching unprocessed horse leather. In the front edge of the dash is a 10.1 touch-screen monitor. This monitor displays vital system information and is connected to an on-board computer system.
Moving forward with the construction of the interior, Buwalda ran all of the vehicle’s wiring – both audio and OEM, up through the A-pillars. The pillar covers are made entirely of fibreglass and pressure fit in place. The OEM wiring runs inside the pillars while the audio system wiring is on the outside. This ensures nothing is on the floor of the vehicle which could possibly vibrate, rattle, buzz, hum or otherwise detract from the acoustic experience.
Continuing on the effort to provide a silent listening environment, Buwalda fabricated custom door panels from MDF and fibreglass. There are no switches or controls in the doors, as the on-board computer takes care of everything. Even the process of opening the door is done via the computer. The new door panels, finished in leather and Alcantara are not only extremely rigid, but add an impressive three inches of width as compared to the stock panels. This helps reduce sound reflections close to the driver and further focuses the soundstage.
The only visible off-the-shelf components in the interior are a set of Sparco Milano 2 seats (which, incidentally, were modified with matching leather inserts), a Globe R shift knob, a Faster steering wheel, Cromo pedals and racing harnesses. Everything else was upholstered in black Alcantara Suede and saddle leather over custom made panels. The carpet is real English Wilton Wool, not surprisingly, imported from England.