Fuel Pressure

[AZ3.8Camaro]

I have a basic question first...
Whats the highest fuel pressure you will see on a 3800S2 motor? I mean, sure you can up the fuel pump, but at what point does the fuel pressure regulator max out?

The highest I can get is 90 psi.

Now the advanced...
How can I make it go higher? Can I alter anything or reprogram anything to make the car see more pressure?

For some strange reason, even with the walbro I am having the dreaded "dry kit cutout" problems.

I tried a .42 bypass jet, and then a .55 and the fuel pressure went right to 90psi every time with both jets.

At Idle I pick up 45psi or so, and it doesn't move with the throttle.

Magnus has the GTP FPR, how i sthat superior to ours?

[ September 19, 2003: Message edited by: AZ3.8Camaro ]</p>

[John_D.]

I'm not sure I understand all of the question(s)... I talk through some of what I know, and see if that helps any.

When spraying, I see about 70 psi on mine, that's with a boost-a-pump engaged at 30%, and a very small bypass jet (around a 28).

At idle (vacuum = 20) it's closer to 40 psi. Under load (vacuum = 0), the fuel psi goes to around 48.

A bigger bypass jet will apply less pressure to the port on the fpr, and will cause less fuel pressure. To get more fuel pressure on a dry kit, you need a smaller bypass jet rather than a larger one.

Injector flow becomes erratic beyond a certain psi. Kenne Bell has an article on the superchargersonline.com site, stating this starts to happen somewhere around 65-70 psi.

If your fpss is cutting off the nitrous, upping the pressure even more than 90 psi is probably not the best solution. You may have a faulty fpss.