Return Fuel line questions...

[importhonda]

No from what I understand a return fuel line allows for extra fuel pressure to be available for nitrous kits...

In our cars how does the car know to increase fuel pressure whe squeezing?

I was thinking about doing a 75 wet shot, but wanted to figure out how it all was goin to work?

[bioevolve]

Correct me if I'm wrong, If you use the NX kit which has n2o and fuel(being tapped) spraying in the intake, the fuel pump compensates for the drop in pressure going to the injectors. Also the fuel jet side adds the needed amount of fuel for the size of the n2o shot. If you use the correct n2o/fuel ratios.

[importhonda]

but think about it this way... when you have a return fuel line, you have maybe 70psi extra worth of fuel ready to be tapped... now if you are strictly depending on the fuel pump to deliver the extra psi it will take the pump a few seconds to get that extra pressure to the front of the car to your injectors... that means your are squeezing without extra fuel pressure which can't be good for the engine.

[bioevolve]

I just guessed, I don't think about stuff like to much. Just do it and be happy.

mamijdm did dyno runs with fuel jets lower than recommended by NX and the car was still running pig rich every time without detonation due to lack of fuel.

[DAYTONASI]

The 02 SI has a returnless fuel system. There is no return line. If
there was a return line and you took fuel from there it would effect the pressure of the system the same way as if you took it from the supply line.

[pocketrocket]

The pump will have time to adjust, seeing as the actual amount of fuel being added isn't all that great. It would be like crusing along and then mashing the throttle, there's enough pressure in the fuel system (about 45psi - 50 psi on my rail) to support the sudden surge in the requirement for fuel. If you want the real technicalities of the system, call NX or Holley (NOS).

Good Luck and Spray Much!
-PR