This document is currently unfinished.

Note: Installation is intended for qualified individuals. This manual is not fully detailed, as some operations should be familiar for an experienced VQ35 Technician.

Note: No fittings come tightened from CJM. Properly torque every fitting in the entire system. Some fittings come preinstalled, but they are not torqued. Do not over-torque fittings as component damage can occur. Aluminum parts can strip out and be damaged by over-torqueing very easily.

NOTICE: CJ MOTORSPORTS IS NOT LIABLE FOR ANY DAMAGES TO THE VEHICLE THAT THIS SYSTEM IS INSTALLED ON. THIS IS A RACE ONLY KIT AND IS INTENDED FOR EXPERIENCED INSTALLATION AND MAINTANCE WITH FREQUENT CHECK-UPS AND INSPECTION. FUEL INJECTION SYSTEM FAILURE OR LEAKAGE MAY RESULT IN ENGINE DAMAGE OR ENGINE FIRES THAT CAN DESTROY THE VEHICLE OR RESULT IN DEATH. INSTALLER IS RESPONSIBLE FOR SECONDARY INSPECTION OF ALL COMPONENTS FOR MANUFACTURING FLAWS BEFORE INSTALLATION.

You may wish to purchase a new pump seal o-ring from the Nissan dealer, as they sometimes expand to become useless, therefore delaying reassembly.

If you find any missing steps, please let us know so that we can update this page and improve on it.

Step 1: Disassembly

Make sure that the car has less then 1/4 tank of fuel before starting the installation.

Leave the car sit for several hours before beginning installation. This is to reduce fuel pressure held in the system and allow for cooling of the engine.

Remove Strut Tower Bar.

Remove Engine Cover.

Remove Air Intake Tube that attaches to throttle body.

Disconnect Throttle Body electrical connector. Optionally remove throttle body.

Remove EVAP Purge Solenoid Vacuum Line.

Remove EVAP Purge Solenoid Mounting Bracket Bolt and Electrical Connector. Then thread the bracket bolt back into the plenum by itself so that you do not loose it.

Remove the final vacuum line connecting the EVAP Purge Solenoid to the metal pipe attached to the Fuel Pressure Damper Bracket. 

Remove Brake Booster Vacuum Line from plenum top.

Remove Misc brackets from plenum collector and reinstall the bolts by themselves so that you do not misplace them. The bracket shown in the first picture will need to be unbolted from the timing chain cover as well. 
 

With a rag in hand, remove the bolts attaching the fuel pressure damper and inlet hose from the fuel sub-tube. Be prepared for fuel leakage, as the system may still be under pressure. Pull the damper upward very slowly while surrounding the area with a rag to prevent fuel spray. Not a whole lot of fuel will come out, but it may come out under pressure and spray.

From underneath the vehicle, by the passenger side exhaust manifold, disconnect the fuel hose that leads to the damper you just removed. You will need to slide off the safty cap and then you can disconnect it. Fully remove and discard or store away the fuel feed hose with damper, it will no longer be used. 
 

Remove all 18 bolts attaching the upper plenum. Follow REVERSE numerical order of this illustration.

Remove the first throttle coolant hose shown by the arrow in the illustration. You may wish to plug it with a bolt if it is leaking. Slowly lift the plenum off by the front and notice the final coolant hose on the bottom under the throttle. Remove that hose (and plug if needed) and place plenum aside. Be careful with the gasket, it cannot be taken off yet. 

NOTE: From this point on, it is very important that you do not drop any hardware or tools. Should you drop something small into one of the intake ports, and the intake valves are open on that cylinder, you are at risk of losing something inside the engine that will not be retrievable without complete engine tear down.

Remove the PCV hose from the plenum collector as shown by the lower arrow. Then remove the 2 bolts holding the fuel pressure damper and tube bracket as shown by the 2 upper arrows.

Remove the bolts in the opposite order shown in the illustration. Set aside the gold PCV channel cover. Set aside the upper plenum gasket.

Lift the plenum collector off the engine carefully. Cover the 6 intake ports with tape to prevent anything from being dropped inside.

Remove all 4 bolts holding the fuel rails to the intake runners.

Carefully lift the fuel rails and injectors off the intake manifold. Look for any seals or o-rings that may have come off the bottom of the injectors and stuck into the 6 injector ports of the intake runners. If any came off, then place them back on their corresponding injectors.

Enter the interior of the vehicle. In a 350z, the fuel pump access panel is located in the large compartment behind the passenger seat. Remove the floor of the compartment by popping it up in the front and pulling it out. There will be a sheet of sound deadening material to set aside. In a G35, the pump access panel is located underneath the back seat on the passenger side.

When you reach the access panel, rotate the 4 clips 90 degress clock-wise.

Disconnect the harness connector and the fuel feed tube's quick connector. Have a towel ready to absorb some fuel from the connector when it is removed. If excessive fuel drips from the connector, it will remove the corrosion protection coating on the top of the gas tank. You can zip-zie a dry rag to the connector to collect remaining fuel as you push it aside to work in the fuel pump area. 

Remove all 6 fuel pump assembly metal retainer bolts and set aside the metal retainer ring. Gently lift the pump assembly up an inch or so and get the black sealing o-ring out of there immediately. You can gently get the O-Ring over the top of the assembly with very little stretching by using care. The O-Ring will expand and be unusable if it contacts gasoline.

Gently navigate the assembly out of the fuel tank. Handle with care to prevent bending or damaging the fuel level sensor sending unit or float arm. Be aware of the fuel siphon hose that is connected to the fuel pump assembly on the side that faces the rear of the vehicle as you lift it out. When the assembly is a couple inches out, you can remove the siphon hose and drop it into the tank. If needed, you can rotate the assembly 90 degrees counter-clock-wise to ease removal of the siphon hose. 

Place a towel under the pump assembly before carrying it away from the gas tank opening to prevent spilling gasoline in the vehicle interior.

With the pump assembly outside of the car, the dissassembly phase is complete.

Step 2: Fuel Pump Modification and Installation

Un-snap the black fuel temp sensor on the bottom of the can and unsecure its 2 wires from the canister. Remove the lower surge can off the assembly by releasing the snap lock and sliding them apart (pay attention to how it slides on/off to make reassembly easier). Take care not to damange the level sensor as there are 2 wires attached to it. You can pull the two terminals off the level sensor and set the entire can aside if you wish.

Step 3: Fuel Rail and Injector Installation

Step 4: Fuel Pressure Regulator Installation

Install the regulator in the location shown. Before making installation permanent, set upper intake manifold parts on to make sure the regulator position is clear of the throttle body inlet neck and the EVAP solenoid. Also make sure there is enough clearance for any gauge or sensor you plan to use in the 1/8 NPT pressure port on the front of the regulator. Install included gauge now if desired.

Step 5: Hardpipe Adapter Installation

The hardpipe adapter is used to adapt the factory 5/16 hardpipe into an AN style connection. This allows you to install performance plumbing to the OEM hardpipe. The hardpipe adapter kit consists of 3 parts. Part #2 will be inside parts #1 and #3 in your package.

CAUTION: This step involves extra care to prevent injury or fire. When cutting the hardpipe, remember that there is still gasoline in there. Wear eye protection and do not generate any sparks while cutting.

Seperate the parts into 3 individual items. Installation requires you to cut the factory hardpipe. You want to cut it just before the bend that goes upward towards the headers. Cut it immediately before the bend to give yourself as much straight section as possible. The 2nd picture above shows where it will go (The arrow indicates location, but the photograph is taken of a Stage 2 system with upgraded hardpipe). DO NOT CUT THE WRONG PIPE, make sure your not cutting the EVAP pipe.

After cutting the pipe, you need to trim back about 1.5" of the plastic coating. This is most easily done with a razor blade. Use it as if peeling a carrot, starting at the cut edge and sliding down the pipe for the 1.5". After removing the coating, you need to prepare the pipe for use. Use a file to make the edge straight and perpendicular. Then use deburring tools or sand paper to deburr the end. Once properly deburred, part #2 should easily slide on and off.

Once deburred, begin installation by sliding item #1 down the pipe facing the direction illustrated in the first picture above. Then slide on part #2 facing the direction shown in the picture, with the externally tapered edge first.

With items #1 and #2 loose on the pipe, install item #3. It will thread into item #1. You want to firmly press item #3 up against the cut edge of the hardpipe while you tighten #1 against it. This will crush the compression fitting (#2) and create a seal. You need to make sure that you do not accidently compress item #2 while its not fully on the hardpipe.

This fitting takes a LOT of torque to seal. You are better off to start mildly tight, and if it leaks during pressure testing then you can torque it more. Pay lots of attention to this union for leaks during the pressure testing phase. If correctly installed, this adapter will be a leak free solution that will last forever. Be careful not to kink the pipe near the adapter, and do not ever open it later unless removing for good.

Step 6: Hose Installation

Step 7: Purge Debris and Pressure Test

It is highly recommended that you perform this step now, rather then after the car is running again.

To purge debris, you want to run your return line into a bucket and prime the fuel pump 4+ times to push any debris thru the system and into the bucket.

While doing this, you can also inspect all the lines in the engine bay. It is very important that you have absolutely zero leakage anywhere in the engine bay. Raise the regulator pressure to increase pressure in the system while checking for leaks. You need to check at every fitting and every crimp.

Step 8: Install Intake Manifold and EVAP Line

Step 9: Bleed Coolant

Step 10: Set Pressure

Prime the fuel system and set the fuel pressure at the regulator. This is done by loosening the lock nut on the top, and turning the allen screw, and retightening the lock nut.

Step 11: Tune Vehicle

A RFS will completely alter the fuel pressure characteristics in your vehicle. A fresh tune is required after installation

This is not a complete installation guide, this is just some notes to help the installer.

Wiring Information

You will need to cut the level sensor wires off of the factory assembly. Cut them as close as you can to the top to preserve as much length as possible. You will crimp one of the provided terminals to each wire, then insert them into the connector on the inside of the pump assembly.

The factory assembly has a temperature sensor. This is not used in the CJM assembly. To prevent a Service Engine Soon light, you will need to purchase a 2.4K Ohm resistor and wire it in-line (outside the tank) to replace the sensor.

Carefully route the slack on all wires inside the assembly. You do not want them in contact with any sharp edges that would wear away at the insulation, such as a hose clamp, as the vehicle vibrates.

You will need to use the factory fuel pump power wires to activate a pair of relays that you will use to power the twin pumps. This means running a decent gauge power wire from the battery to the relays and then to the pump connector.

IMPORTANT NOTE ON STAGING THE FUEL PUMPS; If you desire to stage the fuel pumps, that can be done. But it is important that you correctly wire which pump is the primary and which is the secondary. The primary pump MUST be the pump that is closer to the transfer siphon barb on the bottom of the canister. This pump runs the transfer siphon, which is why it needs to be in full time use. The other pump that has the hole in the can underneath it will be the secondary pump to engage under high load.

Summarized Recommended Wiring Parts List:

Terminal Installation

Note: Use a Volt Meter to make sure you are inserting terminals in the correct port of the plugs. You do not want to accidently reverse polarity of the pumps or send 12v to the level sensor.

CAUTION: While the plugs that go on the inside and the outside of the wiring bulkhead are identical, the one that goes inside the tank must be prepared. The rubber dust seal behind the terminals and the slider dust seal must be removed. If they are not removed, they will expand and extrude into chunks of rubber to clog your pump pickups. Please verify that the connector plug you are going to put on the inside of the bulkhead does not have any rubber inside or out. Also, the sliding safety lock needs to be removed from the connector that is being used inside the tank. This should have already been done for you, but please verify.

Remove the blue Terminal Lock by
pulling outward with needle-nose pliers.

This is what it looks like with the Terminal Lock removed.

Insert crimped terminals into the back of the connector as shown. 
Either flat side can face up.

Slide the terminal in until you hear/feel the click.

These connectors feature a safty lock that prevents them from being pulled off. 
This photograph shows the unlocked position.

This photograph shows the LOCKED position.
The connector cannot be removed in this position.

Plumbing Information

The twin pump assembly comes with no plumbing outside the tank. There are several ways to plumb this assembly based on the vehicle owners needs. We do offer a twin pump plumbing kit to adapt the twin pump assembly to our Stage 2 kits, creating the Stage 3 kit. Feel free to contact us about a Stage 3 plumbing upgrade.

To adapt the CJM Stage 1 or Stage 2 return fuel hose to the twin fuel pump assembly, you can use Earl's part number 921106ERL or a similar product.

The OEM fuel filter is located inside the OEM pump assembly. Since you are removing this OEM pump assembly, you may want to install an inline external fuel filter. We do with our Stage 3 upgrade.

The pump output fittings on the top of the twin pump assembly are -6 and facing straight up. Therefore you will need a pair of 90 degree -6 hose ends. Then you will need to run those 2 lines under the car and go from there. We would recommend running them into a Y fitting and using a single -8 or -10 up to the engine bay.

You will need a -6 return line to support the twin pumps.

Walbro GSS342 Installation (350z, G35, FX35, etc)

Note: Installation is intended for qualified individuals. This manual is not fully detailed, as some operations should be familiar for an experienced VQ35 Technician.

This is divided into 4 sections.

1. The Pump
2. Swirl Jet Modification
3. Regulator Modification
4. Final Assembly

Part 1: The Pump

Remove the 2 wires from the 3 clips so that they are loose. Pull up the locking tab on the right so that you can gently pull the unit apart. Be careful not to pull too hard on the wiring. 

Place the 2 spings aside. The unit should look like this when seperated. 

Use a screwdriver to pop the pump cap off the locks and remove the cap. 

This is the unit with the cap removed. 

Remove the electrical connector from the pump.

The pump is ready to slide out, downward.

Pump removed.

Walbro on the left, removed stock pump on the right.

Swap the top seal to the Walbro (Right arrow). Remove the sock by focusing on removing the round metal lock (left arrow).

Put the sock on the Walbro, and put the metal lock on the Walbro. Be careful, the metal lock is hard to get back on, and very easy to loose if it gets away on you.

Slide the Walbro back into the assembly. Make sure you feel the top seal slide into its position. Plug back in the electrical connector. 

Use side-cutters to remove 3 of the 4 tabs on the bottom of the walbro (reference next picture for which 3 of the 4). Do not cut too deep or you will destroy the pump by opening a hole for it to leak. You want to cut them off almost flush. You are safer if you cut them high and file off the rest. Be cautious, the plastic cracks easily and if you crack it anywhere other than cracking the tabs off, the pump is ruined. You can even elect to file this all the way if you want to be extremely careful... filing it is messy so if you choose that route then take the pump back out so you dont get a mess of plastic everywhere and use compressed air to blow clean the sock. 

Pump with 3 tabs removed.

Mark this part of the pump cap to file off. Notice the green marking. 

Use a file like this and file off the area marked.

With some muscle, starting on the left and working your way to the right, reinstall the pump cap onto all the locks. It can be done at this point but if you feel that you just cannot get it to snap and lock SECURELY on, you can file other sections down to allow more room. Just be careful, if you file too much then the pump will fit loosely, you want it extremely snug and you want to make sure the cap is correctly seated so that it does not pop off. It should be flexing just a little to get on. 

Pump installation is now complete, however, do NOT skip the following steps for pressure control. 

Part 2: Swirl Jet Modification Procedure (REQUIRED FOR GSS342 or larger pumps)

If this step is skipped, your idle and low RPM/Load fuel pressure will be high and cause tuning grief. This will address the issue and is required WITH or WITHOUT a return fuel system.

Carefully remove the yellow swirl jet from the bottom of the can. Do not break it, its just cheap plastic. 

Drill the outlet to .070". If you are using a larger pump like the DW or the Aeromotive, a .100" might be a better idea. Its very soft plastic and drills easy, be careful not to drill all the way through the entire part or it is ruined and not replaceable. Just drill until you can look into the large opening and see the drill has made it to the chamber.

Making sure the o-ring is still in place, snap the jet back into the can. This step is complete. Follow the next step if you DO NOT have a return fuel system. 

Part 3: Regulator Modification

If you are installing a return fuel system, then skip this entire step and begin installing the return correction kit. This modification is only needed if the OEM regulator is going to remain in place. Return fuel systems eliminate the OEM regulator.

Remove the regulator cap. Remember, its just plastic, dont break it. 

Remove the regulator. Just put a screwdriver under the lip and twist, it pops out easy.

Using a 7/64 drill bit, open the regulator outlet oriface. ONLY drill until you make it thru the sheet metal.

Blow the regulator off with compressed air. Making sure both o-rings and the plastic spacer are in place, reinsert the regulator into the housing and reinstall the regulator cap. 

Part 4: Final Assembly

Reinstall the 2 assembly springs.

Reassemble the housing. It helps to use one hand to compress the filter sock. Dont pull out the wiring. Make sure you get it all back into place and when done properly the housing can be compressed by hand and it will naturally fully extend to its natural position when you let it go. Resecure the wires to the clips on the housing.