If anyone is going to buy an NX kit or already has one and hasn’t upgraded their fuel system this may help you decide what to buy. Any shot over 75 HP wet should have the fuel system upgraded to ensure adequate fuel.

Fuel requirements are much much different for a wet system than dry because NX operates at stock fuel pressure. You can use a 190 lph pump vs the 255 lph Hi Pressure one required for dry systems. You can also retain the stock Fuel Pressure Regulator. You will probably save at least $150 ($125 FPR & $25 less for the 190 lph pump).

The 190 lph pump will flow the same volume of fuel at 50 psi (stock press is 43 psi at WOT) as the 255 lph Hi Pressure pump will flow at 80 psi (press required for an 80 HP dry shot). The 190 lph pump will be easier on your system because of the reduced pressure and flow as well. It will support well over 500 HP so you won’t starve it for fuel.

I have attached the chart from Auto Performance Engineering to show the flow rates for the pumps and have circled the two volumes indicated above. They are also an excellent source to purchase from.

http://www.autoperformanceengineering.com/

The one that fits the Maxima is the FPD004 for $88 vs the FPD006 at $113 which is the one used for the dry system. They do not show one for the Maxima but it is the same as the one shown for the 95-98 Talon/Eclipse.

Unfortunately for me I already have the 255 lph Hi Pressure one and the FPSS that I purchased for my dry system but my Son just bought a 98 Talon TSI and wants both so I will now just get the 190 lph one.

 

Jim:

When running > than a 75 shot with NX kit, is the upgraded pump required to support the additional flow of fuel?

My guess is that the engine is pulling sio much fuel that the stock pump cannot keep up...correct.

Might seem kind of obvious to some. I will go no higher than a 70 to begin with.

Is there any way to test the stock pump to see how well it is doing its job or is this really not required with this kit?

Dave

 

Even with the 190lph pump, you might still need a FPR. I will able to confirm this once I get my mechanical fuel pressure gauge. According to my eletrical fuel pressure gauge, I'm about 4 psi too high at idle and WOT.

 

Dave
The only way to know is watch the fuel pressure gauge, I tried a 100 shot on the stock pump and it was ok, but I wouldn't recommend it.

Lots of people run a 50 shot NOS with the stock pump and the stock pump is bumped up to over 60 psi. At that pressure the stock pump would have its volume reduced much more than running a 75 shot at stock pressure like on a wet system.

I wouldn't run any kit at any shot without a fuel pressure gauge or egt,

1MAX2NV
I gues there are exceptions to every rule, I was able to run the 255 lph Hi Pressure pump without an FPR.

Also make sure you check your fuel pressure before you put the pump in, the stock pressure may already be higher or lower that it should be. I installed a kit on one guys car who was running 50 psi stock at WOT. Make sure you know where you are first, it may not be the pump thats increasing your pressure at all but a faulty fuel pressure regulator.

I have been looking to see if anyone has been using C16 with nitrous, we have some local guys here who run it quite sucessfully in their Hondah's

This year I am planning on running a 1 gal fuel cell under the hood with a separate pump to supply the fuel for the nitrous nozzle and running C16. It does wonders to remove any concerns about detonation with high hp shots. I will be using an OBD-II analyzer as well to keep an eye on things while I work out the bugs. Got a S-AFC in the works too.

 

I was told at a performance shop that NX was plug and play. I didn't have to worry about fuel pressure because NX was wet and had it's own gas solenoid. He was wrong huh? Thanks for answering my nitrousnewb questions.

 

For the most part it is. It uses stock fuel pressure. This post is referencing going over a 70 shot.

Over a 70 shot you may need to upgrade your fuel pump as it may not be able to keep up with the fuel requirements. It still uses stock pressure but, you will be using alarger volume of fuel at a quicker rate.

Dave