NA S4 stock fuel pressure and injector specs
 

Hey guys,
I am about to start using 460cc NA S4 injectors (part# 195500-1350) on my 280ZT project. I looked in the FSM in linked in your FAQ, and it says that the fuel pressure at the rail, with the car off and pump on, is 34-39psi. Is that usually closer to 34 or 39? 5psi is a much larger range than I was expecting. It doesn't say what it is at idle, either- does anyone have an approximation? I realize the volumetric efficiency at idle on a 13B and a L28ET is not exactly the same, but I would like it for reference anyway.

Also, does anyone know what the injector opening times are?

Thanks,
-Forrest
http://www.wanganmidnight.com/forums...ODE=12&CID=130

Not absolutely positive on this but

I believe regular running rate is 28psi.
The Hotstart solenoid vavle turns on during startup/hotstart to make the fpr go to 38-40psi but is should go down to 28 if I'm right.

28psi is the idle fuel pressure. The static fuel pressure (which is the pressure the injectors' flow is measured at) is approximately 37psi but there are always variations from car to car, hence the specs.

Injector opening time varies massively depending on load and rpm.