SY732

FPSS digram shows the white wire from relay #85 to the FPSS then to ground.

The main diagram shows the yellow first stage wire from the window switch to #85 on the relay.

What are my options, I have the fuel noid mounted next to the fuel rail and grounded thru an intake bolt right next to it and the window switch is in the glove box.

TIA

Ray@Nitrous Outlet

the FPSS can be put inline between pin 85 on the relay and the window switch.

SY732

So then I need to loop it back to the relay and not ground it right?

Todd157k

iTrader: (5)

no, not to ground.
Take your yellow wire from the window switch (that originally was to go to pin 85) and go to one side of fpss. The other side of fpss goes to pin 85.

Ray@Nitrous Outlet

may not be exactly the same components you zare using but it shows the FPSS and window switch

SY732

Thanks

waterbug1999

iTrader: (3)

What PSI you setting it at?

I have mine as well but have not installed it. I was reading 63PSI on my guage on the fuel rails, so what should you dial it in at?

Can I use an air fitting and adjustable air regulator to dial it in? Thanks

SY732

I dont know any help setting it up guys? 06 C6

Says it is set at 35psi???

Todd157k

iTrader: (5)

pressure directly effects flow rate. Most posts have said 35psi (and I think that's where mfg set them at) as a minimum. I used 45psi because if my pressure is dropping at all, I want the damn thing off. Lean is not your friend. And yes, use the air pres. to dial it in.

waterbug1999

iTrader: (3)

How much should the fuel pressure drop when at WOT and spraying VS at idle?

Ray@Nitrous Outlet

ideally you don't want to see any pressure drop but mast cars will see a ~5-7psi drop upon initial activation.....the FPSS is designed to be a shutoff in the case of a major drop in pressure

waterbug1999

iTrader: (3)

I understand that portion... I just dont know how much of a fuel pressure drop will result in a lean status then a potential melt down.

I see 63psi at idle. So, would it be safe to set it at 55psi?

Ray@Nitrous Outlet

I would have it set ~50PSI

waterbug1999

iTrader: (3)

Thanks.

waterbug1999

iTrader: (3)

OK... I finally dialed the switch to ~50psi.. A question on the wiring. Since the FPSS will be mounted right next to the N20 soleniod, can I just run the FPSS in series with one of the N20 wires?

If the FPSS runs below the dialed in pressure it will just cut the curcuit and no more juice. Will this work?

Todd157k

iTrader: (5)

I think 50psi is a little high, but up to you. You can use the fpss on the noid line however noids draw a lot of current. If you're using some of the new "big" noids, it may not be able to handle that much current. If you MUST put it there, use another relay. I would suggest just running lines and stay off the noids.

SY732

I just ran the yellow wire from the wot switch to the FPSS then to the relay #85.

waterbug1999

iTrader: (3)

I guess ill just put it in series with #85 then.. I am running at 63PSI at idle off the rail. So, does the fuel pressure drop ~13psi under WOT?

SY732

I would think you would want it closer like 55-58psi.

Put a fp gauge on the fuel rail and test the drop.

I assume if it is too close (high) it will hit stumble (shut off) and hit again is this bad? what if it happens once then you adjust it?

Ray@Nitrous Outlet

the thing is...the FPSS is designed to shut the kit off in case of fuel pump failure, not fuel pump hp limitations. Not saying it won't shut it down because the pump can't keep up....but you can create more headaches by setting the FPSS to high.

There is not a set psi that it needs to be set, each car is a little different...that is why we tell people to set it on the car with the kit activated...this is setting it to the flowing fuel pressure, not the static pressure.