Here is what someone on the other board said.

Opinions?

NO!!!! Bad idea.

I tried it once, promptly put it back behind the solenoid.

What will happen... fuel will open... and spew unatomized liquid gas into your bellows and intake.

The car will begin to bog HEAVILY, then when the nitrous solenoid opens up you will wind up with a MASSIVE cloud of black smoke behind your car, and VERY possibly a large backfire.

It is NOT a good idea to have fuel puddled up in your bellows / throttle body / intake manifold.

Dont do it.

What happens when it's behind the solenoid???

It will cycle the solenoids on and off until the fuel line is full of fuel. It works a bit better for traction out of the hole.

What happens with no FPSS???

Fuel pressure drops 15 to 20 psi for a split second and jumps back above 50psi, this DOES create a temporary lean condition.

 

To help stop the lean condition on the intial hit try a shorter fuel line between the solenoid and the nozzle or power ring. Leave the n2o line long. This will help stop the lean condition. You can have a rich condition back fire I have seen open header cars with wet kits I.E. fogger or plates that either didn't have enough bottle presure or n2o solenoid failed and dumped raw fuel in to the manifold and it will back fire the exhaust not out the intake like the lean condition. It will ignite the raw fuel in the exhaust. Fpss in my opinion are not worth any thing if your car don't have fuel pressure it won't right to begin with if your car isn't running right don't spray it! If your fuel solenoid dosn't open your car should get a lean bog get off the juice. Nobody said n2o would be safe you need to maintain your system there is no real safe way. just my opinion.

 

For a wet kit. I'd reccomend getting the proper fitting and installing a LOW pressure (5psi adjustable) AFTER the fuel solonoid. And grounding the nitrous solonoid through the FPSS. This way the fuel solonoid will open, fuel will flow through, the FPSS will see fuel pressure and then allow the nitrous solonoid to open. And it might even minimize that lean spike from the nitrous hitting the motor first (nitrous at 900-1200 psi, compared to 50 psi of fuel pressure.)

If you set up the FPSS at the fuel rail or before the fuel solonoid it just makes sure the fuel system is up to the task. But the fuel solonoid could still not open.

To be very safe you could run two FPSS's. Run one HIGH pressure (40-60 psi adjustable) at the fuel rail before the fuel solonoid and run a LOW pressure (5 psi adjustable) after the fuel solonoid. You ground the fuel solonoid through the first HIGH pressure one and ground the nitrous solonoid through the second LOW pressure one. Can't get much safer then that.