Fuel-pressure regulators are fuel-pressure regulators are fuel-pressure regulators, right? Wrong! While they all accomplish the same purpose, there is a big range when it comes to price, material, fuel type, and other options. There are fuel-pressure regulators for all kinds of street performance and motorsports, including circle track racing. An Outlaw drag car with three stages of nitrous has very different needs than a Street Stock with a small two-barrel carb, and there are options for everything in between. Deciding what your best options are, is going to come down to your specific combination.

Whether you run a carburetor or EFI, pump gas, or methanol, there are regulators out there to fit every need. It’s a safe assumption that as your fuel system needs get more complicated, horsepower gets higher, and fuels get more exotic, you’re going to need a better, more expensive fuel-pressure regulator. But what separates a $20 regulator from a $300 regulator? After a conversation about just that with Curt Spalding from Allstar Performance, we decided it was worth taking a more in-depth look.

Making a decision on a fuel-pressure regulator will be largely based on your specific needs. Companies like Aeromotive, Allstar Performance, Holley, and Summit Racing offer many different regulators, with many different configurations and options. These options will be based on what fuel you run, whether you want to run a return or returnless style fuel system, how many ports you need, and whether you run a carb or EFI. To start it all out, we are going to take a look at the basics of fuel delivery so you have a solid general understanding of how it all works.

Fuel Delivery

In every fuel system there are some key components—the tank or fuel cell, fuel pump, lines, regulator, and carb or fuel rails and injectors. Filtration is also extremely important, but that can be a story by itself, and we aren’t going to get into that here.

Without getting too off track, it’s important to take what you are doing in mind when designing your system. In circle track racing, lateral g-forces can move the fuel to one side of the cell in the turns, so it’s important to have the fuel pump pick-up in the correct location, so the pump isn’t starved when the fuel moves in the cell. Pump, lines, regulator, and method of delivery (carb or EFI) all need to be taken into consideration when choosing line size, filter size, pump capacity, and so on. Knowing what you have and looking at your goals is important. Skimping on one piece of the puzzle could mean replacing the entire system later if you decide to make more power.

Volume vs. Pressure

Volume and pressure are two completely different things when you talk about fuel, but they must work together to give you the proper air/fuel mixture delivery. Both carburetors and EFI systems require the proper fuel volume to make the desired horsepower, but the pressure differences between the two are quite different. A carbureted setup requires very low fuel pressure—somewhere between 5 and 9 psi, while an EFI setup, on the other hand, could require as much as 60 psi on the high side. This means the fuel pump needs are entirely different, and regulating pressure is different as well. Regulator manufacturers make regulators specifically for each application.