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# What is a rising rate fuel pressure regulator?

## What is a rising rate fuel pressure regulator?

Rising Rate. If the fuel pressure regulator (aftermarket or OEM) is connected with a vacuum hose to the intake manifold, then regulator is a 1:1 rising rate. This means that fuel pressure increases with boost and decreases with vacuum at a 1:1 ratio.

What pressure should the fuel pressure be set at the regulator?

For a GM, this pressure is usually set to 58psi (factory fuel pressure in the rail). The vacuum/boost referenced regulator will help to change the pressure in the rail based on the pressure in the manifold. When an engine is idling, it may be pulling 20 inHg of vacuum, which translates to roughly 10psi.

Does increasing fuel pressure increase power?

Changing the fuel pressure on an EFI System is an effective method of affecting engine performance and making more power.

### Does fuel pressure regulator increase horsepower?

By tuning the regulator and getting an optimal air/fuel mixture you can acquire a few HP. But like I said, unless you already have a problem, it’s not going to be of any benefit.

How do you increase the pressure on a fuel pressure regulator?

When adjusting the fuel pressure, the engine should be at its lowest setting. A screw is held in a fixed position with an Allen wrench while a nut is loosened on a regulator. The fuel pressure can be raised with the help of a screw clock. The way to lower pressure is to turn the screw count clockwise.

What should fuel pressure be at idle?

Idling you’ll be at approximately 15 ~ 20 inches of vacuum which means fuel pressure must drop by 15 ~ 20 PSI to maintain the correct pressure drop across your injectors. In other words 39 PSI base + 20 inches of vacuum at idle = 19 PSI fuel pressure at idle.

#### How much fuel pressure is needed for a carburetor?

Carburetor Fuel Pressure by Manufacturer

Carburetor Style Recommended Fuel Pressure
Autolite 4.5 – 6.5 psi
Holley 5.5 – 7.5 psi
Edelbrock 6.5 psi (max)
Demon 5 – 6 psi (at idle)