ZEX Nitrous Installation (cont.)
Once the bottle position is determined the next step is to route the nitrous supply line. The usual method is to run the line along the underside of the vehicle. We however chose to run the line through the passenger compartment, routing it along the door sill and under the carpet. The kit comes with 16 feet of -4AN line, so you can route it however you want. Just use rubber grommets anytime the line passes through metal.	Proper nitrous oxide performance is dependent upon cylinder pressure being between 900 and 1000 psi. The best way to monitor this is with a gauge mounted to the bottle. We're using a ZEX inline pressure gauge and adapter (PN 82005). A bottle heater can be used to warm the bottle and raise pressure, however in our California climate we should be okay without one.
With the nitrous bottle mounted and feed line routed to the engine bay, we turn our attention to the ZEX nitrous management unit. The unit houses both the nitrous and fuel solenoids, simplifying the mounting and wiring steps. We mounted our unit to the smog pump eliminator bracket as shown. We'll connect the nitrous feed line (red cap) once our purge and fuel feed is connected.	The supplied -3AN nitrous and fuel delivery lines connect to the outlet side of the management unit. There is no problem in how the management unit is oriented. We positioned our unit upside down such that the nitrous and fuel inlet ports face towards the rear of the vehicle - facing the feed lines.
In order to connect the -4AN fuel feed line to the management unit we need to tap into a pressurized fuel source. Unlike most nitrous kits on the market, the ZEX kit comes with a variety of fuel fittings and adapters making it easy to tap into your fuel rail or regulator.	We simply tapped into one of the ports on our Mallory regulator. We connected the fuel supply line and routed it to the fuel inlet port on the management unit.

 

II. Installing the Nitrous Delivery Nozzle
The nozzle needs to mount after the mass-air meter and 6" to 18" before the throttle body. The kit includes a bulkhead style fitting for easy mounting into a stock-style rubber duct. A 1/8" NPT tap is also provided for installation of the nozzle into a metal duct.	We tapped into the 3.5" metal inlet duct between our mass air meter and throttle body (see side bar.) While it is not critical where the hole is placed, be sure to select a nozzle position which makes it easy to change the jets and connect the delivery lines.
Install the nozzle and then the jets before attaching the lines. Don't attach the lines if you haven't installed the jets thinking you'll do it later. Leaving the jets out could be disastrous.	This system includes three pairs of nitrous and fuel jets for 75-125 horsepower. We're starting off with a 100 shot. We'll back the total timing off 2 degrees as suggested and run at least 92 octane.
A good look at how all of our lines are routed to and from the ZEX nitrous management unit.