Trucks are just made for modifying, and one of the most popular modifications is more power. Like it or not, more power always requires more fuel and sometimes the stock fuel pump is not up to the task. There is a new-style pump on the market out to compete against diaphragm and electric-style pumps. This short article will give you an overview of this new pump and how it differs from past technology.
Block-Mounted Diaphragm Pumps
These workhorses supplied fuel to carbureted production cars for over 50 years. They're relatively simple, compact, and dependable, and usually no external regulator is required. The design is "low-pressure, variable-displacement." In layman's terms this means they don't require a pressure regulator or a return line. A few aftermarket units have the pressure increased to extract more flow, requiring a regulator and sometimes a return line. The simplicity of the design is thus compromised.
In-Tank Electric Pumps
EFI-equipped vehicles since the mid-'90s have been sold with "in-tank" electric fuel pumps. These pumps are quiet and work very well in stock applications. Service life is generally limited to 100,000 miles. They don't have the capacity to support engine modifications that substantially raise the engine's horsepower output, nor can they be easily retrofitted into non-OEM applications.
The new block-mounted billet-piston pumps represent the first completely new fuel pump design in over 50 years. The compact design has just one moving part and weighs less than a pound. These pumps work on engines from stock to full-out racers with carburetors or EFI; naturally aspirated, supercharged, or turbocharged; with gasoline, methanol, or E85. The design is a high-pressure, variable-displacement one. It utilizes a pressure regulator but does not require a return line. Less pressure is placed on the camshaft or eccentric with the 150-psi version of the piston fuel pump than a 15-psi diaphragm pump. This is due to the efficiency of the piston's design.
Regulators designed for use with the block-mounted piston pump feature a lightweight ceramic valve made of the same material as aerospace ball bearings, seating directly against a hard-anodized aluminum seat. The regulators are available for all applications, including simple gasoline carbureted applications, optional idle bleed to prevent vaporlock with methanol, vacuum reference for load-sensitive fuel pressure, and boost reference for blow-through superchargers and turbocharged applications. Two pressure ranges are available: 7 to 15 psi for carburetors and 45 to 75 psi for EFI applications.
The Final Word
High-performance trucks are a perfect application for the new pump because fuel tanks do not need to be modified-a traditional siphon-feed, top-entry pickup works fine. No return line or wiring is required, making for an extremely simple installation. Of course this is not a perfect world, and this is not quite a perfect pump. You must have the mechanical fuel-pump mounting boss on your engine to use one.