Thread: Rising rate AFPR

Ya aslong as you have good injectors and enough fuel pump to get fuel to them your good, just get it tuned well. Maybe a meth injection kit to make sure you don't detonate if you are running high boost.

There are also cheap mechanical units. Thats generally what "budget" builds consist of. The factory unit is a rising rate FPR. There is no need to get an aftermarket one, unless you want to set your base pressure higher.

x2

Thanks for the help guys. Just ordered a nismo fpr.

Most efi fpr are rising rate including your stock unit, the reason for this is more a case of "equilibrium" than a "tuning band aid".

For instances most regulators are 1 to 1 ratio meaning that they add 1 psi for each psi of boost. This means if your boosting 20psi and you are using a base pressure of 43.5psi then your fpr should show 63.5psi. The pressure regulator is increasing the pressure of the fuel so that it can overcome the charge in the intake manifold. If the regulator was not a rising rate unit and you decided to boost 37psi with a base pressure of 43.5psi ( which is usually around 37psi with the vacuum hose on) your injectors would have a very hard time overcoming the air pressure in the intake manifold and most likely would not fire at all.

ggood choice on the nismo

I didn't want to go cheap considering it's my fuel system and engine at stake.

Plus, you can't go wrong with nismo.

One question though that I'm still not sure of. Do the DE and DET engines use the same fpr? When I installed my turbo on my de, I was under my own assumption that the de was vac operated, and the det was psi operated. So when I bought my 370 injectors, I bought a set with the stock fuel rail and fpr off a det.

So did I assume correctly? Or are they the same unit?

Almost all modern FPR are rising rate. They respond to pressure, whether it be above or below atmospheric pressure. The DE an DET units will opperate the same. Same with the NISMO unit you ordered.

I would have stuck with stock and spent my money elsewhere.

I would have, but I want the ability to adjust the psi when needed.