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Hey forum need your help again I have a fuel pressure regulator on the way and I wanted to know what pressure to set it at to get the most out of the stock injectors. I have a stock turbo as well running 10 psi, what pressure do I set the fuel at to get the most out of the injectors and if I was to turn up the boost to 13 do I then turn down the fuel pressure to compensate for turnin up the boost? Thanks in advance.

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Just set it to "factory" fuel pressure, then leave it alone.
So that would be around 44psi and even if I up the boost just leave it at that? There is no need to up the fuel pressure? So what is the advantage of having a fuel pressure regulator I thought you would use it to up the fuel pressure a bit in order to gain horsepower and maximize injector usage.

The FPR takes a signal from the manifold so that it maintains a fixed pressure above the manifold. So if you up the boost, the FPR will add sufficient extra fuel, based on the manifold pressure (= boost).

Adjusting the pressure is a useful alternative to fitting bigger injectors. BUT, you need to re-tune the ECU, because upping the pressure will enrich the mixture, and these engines run rich enough as it is without adding extra fuel.

The FPR takes a signal from the manifold so that it maintains a fixed pressure above the manifold. So if you up the boost, the FPR will add sufficient extra fuel, based on the manifold pressure (= boost).

Adjusting the pressure is a useful alternative to fitting bigger injectors. BUT, you need to re-tune the ECU, because upping the pressure will enrich the mixture, and these engines run rich enough as it is without adding extra fuel.

So if I am keeping the stock injectors just setting the fpr to stock fuel pressure will give a slight increase in horsepower and the stock injectors will be used to their potential?

So if I am keeping the stock injectors just setting the fpr to stock fuel pressure will give a slight increase in horsepower and the stock injectors will be used to their potential?

AN aftermarket FPR wont be of any benefit unless you raise the pressure, but its not necessary unless you plan on making more than 220rwkw. Even then you need management. The only exception in a rising rate reg, but even then you will need management first

AN aftermarket FPR wont be of any benefit unless you raise the pressure, but its not necessary unless you plan on making more than 220rwkw. Even then you need management. The only exception in a rising rate reg, but even then you will need management first

Ok here is the story. I really don't plan on making more than 220rwkw in my car, from what I read in the forum thats the safest route to go with my current mods and I dont plan on changing injectors Its virtually stock except fmic, cold air filter with pod, 3.5" turbo back, 255 lph fuel pump, stock turbo boosted up to 10 psi and afc neo. I just want to maximize the stock injectors to get the most flow out of them. So I wanted to now if an aftermarket fpr would benefit any or help me in any way to get the most out of my stock injectors.

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