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I have a Nitrous Outlet Plate kit along with a Fuel Pressure Safety Switch. When dyno tuning my car a few weeks ago we had issue getting the nitrous to kick on. It was easily determined it was my FPSS switch. We ended up bypassing it so we could get the car tuned and everything from there out went smooth.
I now want to get my FPSS functioning properly before going to the track in a more or less non controlled environment. From what I understand per the instructions from Nitrous Outlet I need a Fuel Pressure gauge to adjust it properly. Looking at my setup where am I going to add a fuel pressure gauge to determine this since my Schrader port is being used? Do I need to somehow isolate the FPSS to determine its opening pressure? Also I'm not too familiar with the returnless style fuel system (LS2 GTO), but from what I've been told you can't go by the fuel pressure at key on because is doesn't hold steady. If that is the case, how am I going to determine is system activate without making 50 WOT hits to see if it works? Also to complicate things further I'm running a NOS Mini Progressive Controller tapped into my DBW TB.
Can someone help me clear this up or tell me what I need to buy to make this happen? I'd really like to make it to the track this weekend and get some numbers.
FPSS adjustment...
To adjust, remove rubber plug form the top of switch. Insert the proper hex wrench, turn clockwise to increase set point, counterclockwise to decrease the setting.
Your best bet if you have the equipment to do so would be to hook the FPSS up to an air compressor then adjust the regulator to 45-50psi and with a test light or multi meter hooked up adjust the FPSS till you see the light cut off and you should be good to go.
Other than that would be to have the car running and the system activated flowing through the plate etc.. and then adjust the switch till you see the fuel sputter out of the plate then adjust the switch back about 3/4 to a full turn counter clockwise and it should be set ok. The best way and less hassle would be set it via an air compressor.
Your best bet if you have the equipment to do so would be to hook the FPSS up to an air compressor then adjust the regulator to 45-50psi and with a test light or multi meter hooked up adjust the FPSS till you see the light cut off and you should be good to go.
Other than that would be to have the car running and the system activated flowing through the plate etc.. and then adjust the switch till you see the fuel sputter out of the plate then adjust the switch back about 3/4 to a full turn counter clockwise and it should be set ok. The best way and less hassle would be set it via an air compressor.
-Chris
Thanks, I have an air compressor to do this. Definitely be the easiest.
I assume most LS2 guys use 45-50 PSI for an adjustment point? I know very little on these return less setup.
Honestly, if you have any aftermarket pump in the car at all, do yourself a favor and dump the thing. I have had more people have issues with those stupid things over the last 10 years than I care to even think about. I haven't put one on a car in 8 years now and have installed countless systems.... do yourself a favor, if you don't have a racetronix pump and hot wire system in the car, put one in. That single pump will support 9 second power with nitrous. Just a safer way to go about it.
Anything I just use the racetronix kit as an example. Just upgrade the pump and put a hot wire to it so you have a good power source to run the pump off of... and take the FPSS and put it in the garbage can.
10-19-2015, 12:26 AM
FPSS Issues, help adjusting. 
