In the previous issue, we began to install Zex’s brand-new LS Series Perimeter Plate Nitrous System for 90mm-or-larger intake manifolds on a ’99 Trans Am, which had been previously modified from a 78mm factory intake to an older 90mm intake from FAST. Helping us was LS-engine builder Chris Kirchner. In this issue, we complete the electrical side of the install and upgrade the fuel pump.
Though a healthy factory fuel pump may be adequate, it’s a risk we aren’t going to take. Running a ’99 fuel pump to the edge of its limits on spray is never a good idea, even back in 1999! Therefore, we ordered a Racetronix plug-and-play fuel system, which features a FPA-001 fuel pump assembly and FPWK-017W hotwire kit to supply the extra juice it needs to operate at peak performance. According to Racetronix, this pump will reliably support 550-600 rwhp depending on the motor’s efficiency, operating pressure, and supply voltage.
Racetronix also offers plug-and-play fuel-system solutions for cars with mods upwards of 1,000 hp. Since we will not be pushing the T/A beyond 600 rwhp, this kit is ideal. With a very tight deadline and some issues still to sort out, dyno-testing will be done in the next issue.
Here’s the Zex Perimeter Plate...
Here’s the Zex Perimeter Plate nitrous system. To better blend the fuel and nitrous, Zex incorporated 12 injection points around the perimeter of its plate, which is installed at the intake manifold’s inlet.
This is another look at our...
This is another look at our wiring diagram to show how we have our system wired. The details follow.
This junction is where we...
This junction is where we will be sourcing our power. It’s located beneath the driver-side underhood fusebox. Using the supplied electrical terminals, we cut, spliced, and capped the wire.
Because the supplied terminals...
Because the supplied terminals are a smaller diameter than the factory grounds, we drilled an additional hole into the radiator support to ground the relay.
This relay is what the toggle...
This relay is what the toggle switch inside the car will control. When we activate the switch, it will send power to the relay, which will complete the circuit to the wide-open-throttle switch that dictates when the solenoids come on. Three wire connections—two power and one ground—are shown here; the fourth (power) comes out of the back of the unit.
We fed a power line from the...
We fed a power line from the relay into the interior through a hole we drilled in the firewall. We suggest using a rubber grommet to prevent the wire from rubbing and being cut on the metal. This wire will go to the toggle switch.
Chris created a power line...
Chris created a power line for the toggle switch and tapped into power from the side fuse panel using an available slot that will only be active when the ignition is on.
He then connected the final...
He then connected the final power wire to the toggle switch.
We mounted the switch inside...
We mounted the switch inside the ashtray, since it will keep it out of the way and prevent accidental activation.