Category Archives: AUTO

revive your 1500 series fuel pump

Revive Your GM 1500 Series With An Upgraded Fuel Pump

revive your 1500 series fuel pump


Trucks have been a great starting place for restoration and modification projects. Many automotive brands have offered models over the last 70 years with differing chassis, engine, and drive combinations. If you’re looking for a low-cost option with a healthy aftermarket and restoration availability, you may find the 1997 – 2003 General Motors 1500 series trucks to be a perfect fit for your needs. During restoration, it’s incredibly important to consider replacing or upgrading your GM 1500 Series fuel pump.

Choosing the Low-Cost Budget Truck

Both Chevrolet and GMC half-ton truck lines have multiple trim levels available, different engine and transmission options, and come available in both 2WD and 4WD. There is something for everyone.

This model featured the LS-engine family that started a new revolution that saw these engines swapped into everything. Most restoration projects will choose the V8 models or swap one of them in though.

The 4.8-liter V8 (producing 255 horsepower and 285 pound-feet of torque), the 5.3-liter V8 (producing 270 horsepower and 315 pound-feet of torque), and the 6.0-liter V8 (producing 300 horsepower and 355 pound-feet of torque) were available as options from General Motors, and all three have immense potential for restoration or modification.

Assuming the truck runs and drives, one area of focus should be the fuel system. The truck could have sat at some point in its life, or it could have been a constant workhorse and now have a few hundred thousand miles on the odometer.

Whatever the case may be, the fuel pump and other fuel system components may be on their last legs. If you have concerns with either, now is the time to address them. A new fuel system is key for the next phase of the truck’s life.

Replacing the 1999 – 2003 Chevy & GMC 1500 Series Fuel Pump Assembly

Replacing the fuel pump or the complete fuel pump assembly on the 1500 series trucks isn’t a complicated process. Once the fuel tank is removed from the vehicle, the fuel pump assembly can be taken out from the top side of the tank with simple hand tools.

Some will simply replace the pump assembly with an OEM drop-in replacement, however, keeping the factory design will keep inherent design problems going forward. The factory design uses a problematic venturi design to keep the canister full during hard cornering.

If you plan to build a corner carving truck for autocross, keeping this design will have limitations. The venturi design was used in all 1995 – 2005 GM trucks, vans, and SUVs, which will only allow for OEM-style fuel pumps with limited fuel flow potential.

Combating OEM Design Limitations

If you plan to add more horsepower to your truck, the OEM fuel pump won’t flow enough fuel for a lot more power than the factory level. You can add a larger fuel pump for more flow. Doing so requires the fuel pump assembly to be modified by cutting windows into the sides of the bucket.

This completely disables the venturi function of the OEM housing and the ability of the canister to stay full during cornering or acceleration. It will eventually lead to fuel starvation and overheating of the fuel pump.

Fixing the poor venturi design and adding a larger fuel pump can be achieved by switching over to Quantum’s QFS-A81HV 340LPH (340 liters per hour) drop-in fuel pump assembly. This assembly was designed specifically for the 1999 – 2003 Chevy and GMC 1500 Series trucks to eliminate the problematic venturi canister design found in all 1995 – 2005 GM trucks, vans, and SUVs while offering significantly more fuel flow for larger engines or forced induction applications.

This clean sheet design also allows the fuel tank to be run down to empty as the OEM fuel assembly does.

The assembly uses Ethanol safe PTFE / Teflon corrugated flex hose and Teflon-coated wiring throughout. They are 100% gasoline and E85 compatible. The new design features an updated 40-amp bulkhead connector to handle the additional amperage load of the high-volume pump, plus includes a new float arm, sending unit, tank seal, and 4-way wiring connector.

All QFS products come with a lifetime warranty. There’s no need to worry about paying for a replacement later.

Replacing Just The Fuel Pump

If you aren’t ready for a new complete assembly, you may just need to change the fuel pump only. A previous owner may have replaced or upgraded the assembly. In this case, you just need to add a new pump to meet your goals.

That’s an easy fix with Quantum’s varying selection of performance fuel pumps. Each pump in the line-up offers a different fuel flow to meet your horsepower goals. Check out the chart below to see which pump is rated at the horsepower level you need.

The chart uses the standard of 2.64 horsepower per LPH as the conversion criteria.

Part numberpart descriptionhorsepower support

We Are Standing By For Your Order

If you plan to build or simply restore a 1999 – 2003 Chevy or GMC 1500 series truck, take the time to get the fuel system up to snuff. It’s most likely 20 years old, and if it was a previous work truck, it may not have been well maintained. The OEM design works well for simple replacement, but if you plan to modify your truck it will need a better fuel system.

You can order a better-designed replacement pump or complete assembly from Quantum Fuel Systems, Monday through Friday, 8:00 a.m. to 5:00 p.m. PT, over the phone or browse our extensive catalog. Be sure to contact us via our support page for any detailed technical questions, and we’ll get back to you as soon as possible.

ethanol and fuel pumps

How Ethanol Fuels Impact Your Fuel Pump and Fuel System

How Ethanol Fuels Impact Your Fuel Pump and Fuel System

Ethanol-blended fuels are the dominant force in America’s fuel supply. While most modern vehicles are specifically engineered to handle these fuel blends, many cars, trucks, motorcycles, ATVs, and UTVs can run into problems when using certain ethanol-fuel combinations. The greater concern is that ethanol is harder on fuel pumps and other fuel system components. In some instances, rubber expansion, plastic degradation, and metal corrosion may occur. 

According to the U.S. Department of Energy, more than 98% of gasoline sold in the United States contains ethanol, which is what we likely buy at the pump. 

We will examine why ethanol-based fuels can cause harm to your fuel pump and fuel system and what to look for when purchasing replacement components. But, before we dig into the impact that ethanol fuels have on your parts, let’s understand why they’re used, the pros and cons, and what vehicles can use E10, E15, and E85 ethanol-gasoline blends. 

Quantum Fuel Systems is an industry leader in high-quality OE replacement and performance fuel system components. All QFS products are designed to exceed OEM requirements while utilizing top-tier ethanol-fuel-safe plastic, rubber, and corrosion-resistant materials.

Whether we’re talking two-wheels, four, or marine applications, our catalog has everything to cover your fuel system needs.

What Is Ethanol?

Ethanol, otherwise known as ethyl alcohol, is a biofuel addictive created by fermenting biological matter. If that sounds like your average alcoholic beverage, that’s because it is the same type of alcohol found in most beer, liquor, and wine.

However, ethanol is denatured alcohol and has poisonous additives making it unfit for human consumption.

The process begins by fermenting sugars found in grain starches, such as corn, sorghum, and barley, or other sources like sugar cane and sugar beets. Ethanol production isn’t limited to these sources alone and can be manufactured using other plant materials like grasses, wood, or algae. 

These renewable organic materials are called biomass, hence why ethanol-blended fuels are referred to as biofuels. In the United States, most fuel ethanol is produced by fermenting corn.

Why Use Ethanol Fuels?

The reasoning behind using ethanol-blended fuel weaves complicated economic, geopolitical, and environmental issues together. Ethanol is a renewable energy source derived from domestically produced plant materials and, when mixed with gasoline, can help reduce America’s dependence on foreign oil imports.

There are additional environmental benefits as well.

Ethanol is an oxygenate that enhances fuel combustion, producing lower carbon monoxide and pollution emissions. With that much supporting ethanol, it’s safe to say that ethanol is here to stay, and we’ll need to learn to work with it. 

E10, E15, and E85 Explained

Three primary ethanol-gasoline blends are sold in the United States: E10, E15, and E85. E10 is gasoline containing 10% ethanol, E15 contains 15% ethanol, and E85 uses a variable 51-83% ethanol blend, depending on the region and season. 

Ethanol and Octane

This is where there is some confusion for consumers: The number values next to “E” do not relate to octane. E10 and E15 blends are used to create the 87-95 octane fuels commonly available at gas stations.

Meanwhile, E85 often exceeds 100 octane depending on the ethanol-gasoline. The significantly higher ethanol content and octane of E85 can only be used with engines specifically designed to accommodate it.

Interestingly, ethanol has higher octane than gasoline. However, ethanol is roughly 33% less energy dense than pure gasoline.

That means ethanol can produce more horsepower but is less efficient than gasoline when burned. Less efficiency results in slightly reduced gas mileage when using ethanol-blended fuels.

Vehicle Compatibility

E10 has been sold across the United States for years and is deemed safe for all modern cars, trucks, and Powersports vehicles. While true in most cases, there are some complications related to ethanol that we’ll examine later.

Additionally, we recommend referencing your vehicle-specific owner’s manual to confirm the suitable fuel type and grade.

E15 can be used safely in vehicles manufactured in 2001 and after, according to the Environmental Protection Agency. Importantly, we should note motorcycles, ATVs, UTVs/Side-by-Sides, and marine engines are rarely designed to accept E15 fuel and should not be used.

E85, also known as Flex Fuel, is a high-volume ethanol blend that can only be used in engines designed explicitly for Flexible Fuel Vehicles (FFVs). FFVs are designed to use other fuel grades, but E85 often features high-octane ratings, requiring engineering to compensate for those needs. 

Despite E85 being marketed as an environmental-friendly fuel alternative, E85 is popular among tuners and performance-engine builders for various reasons. Compared to gasoline and lower ethanol blends, E85 features high oxygen content, better evaporative cooling, greater knock resistance, lower exhaust gas temperatures, and much higher octane. 

Those running high-performance engine components can gain extra horsepower by using E85 and adjusting fueling or ECU maps to utilize it properly. In addition to that, you must ensure that your vehicle’s fuel pump and fuel system components are ethanol safe.

QFS offers everything you need to make your performance build E85 ready.

Ethanol Gasoline

Most problems with ethanol stem from the fact that it is hydroscopic, meaning it absorbs water from the air. Gasoline is hydrophobic and repels water.

Ethanol and gasoline can mix, but if the water concentration becomes too high, then phase separation will occur. The ethanol and water will separate from the gasoline and settle at the bottom of the storage tank.

Leaving metal components submerged in water will cause corrosion and damage parts like an in-tank fuel pump, fuel sending unit, strainer, filter, or regulator. 

Worse yet, the ethanol and water mixture becomes a perfect breeding ground for an acetic bacteria known as acetobacter. Acetobacter causes the mixture to become highly acidic. This destructive environment can quickly wreak havoc on components throughout your fuel system.

Vintage and late model vehicles are more susceptible to ethanol fuel issues because manufacturers didn’t anticipate engineering plastics, rubbers, and metals to withstand the corrosive environments ethanol fuels can create. While ethanol has been used as an additive dating back over 100 year, it didn’t gain prominence until recently.

Those who own vehicles with older-style metal fuel tanks will want to take special care when using ethanol gasoline. Older rubber components like O-rings, gaskets, and fuel lines can swell or become brittle and break down. Damaged components lead to numerous mechanical failures. 

OEMs have since transitioned to ethanol-fuel-safe components to avoid these problems. Reputable aftermarket manufacturers like QFS use ethanol-compliant components in all fuel system parts, ensuring that your vehicle will run trouble-free on ethanol fuel blends. 

Preventing Ethanol Fuel Problems & Ethanol Phase Separation Treatment

Ethanol fuels have a lousy reputation among gearheads, especially those running vintage vehicles. Most problems associated with ethanol-blended fuel can be avoided through some simple strategies. 

Phase separation only occurs when a vehicle is stationary for a prolonged period. Most ethanol fuels will experience phase separation in roughly 60 days in a high-temperature and high-heat environment. The easiest solution is to operate your vehicle and cycle fuel through the system to prevent phase separation.

If you store your vehicle for extended periods, treat the fuel with stabilizers or fill it up using non-ethanol fuels. These fuel types can still be found at some specialty gas stations.

Have Any Technical Questions? Our Staff Is Standing By

Quantum Fuel Systems is open Monday through Friday, 8:00 a.m. to 5:00 p.m. PT. Reach out via phone or email to reach our support staff with any technical questions.


  • Ethanol, otherwise known as ethyl alcohol, is a biofuel addictive created by fermenting biological matter
  • When mixed with gasoline, ethanol can help reduce America’s dependence on foreign oil imports
  • Three primary ethanol-gasoline blends are sold in the United States: E10, E15, and E85
  • E85 is popular among tuners and performance-engine builders for various reasons
  • Vintage and late model vehicles are more susceptible to ethanol fuel issues

5 Ways To Maintain Your Fuel System

5 Ways To Maintain Your Fuel System

Outdoor recreation is booming, which means more people are using their Powersports vehicles. Motorcycles, dirt bikes, ATVs, UTVs/Side-By-Sides, snowmobiles, and personal watercraft are racking up hours across the United States as new riders and families join in on the fun. Motorcycle sales alone were up nearly 10 percent in 2021, hitting their highest levels in 15 years.  We’re going to go over five easy ways to maintain your fuel system and ensure it’s in good working order, giving you peak performance, fuel mileage, and reliability.

All that time out on the road, trail, or water does add up, and responsible owners know that to get the most out of our vehicles, they need to keep up with regular maintenance. Even the most diligent owners and DIY mechanics overlook their fuel systems until there is a problem. 

Don’t think these tips are exclusive to your motorcycle, quad, or UTV — these maintenance suggestions apply to any car, truck, or RV equipped with Electronic Fuel Injection (EFI).  These tips are to help prevent fuel pump failure, regardless of vehicle type.

Quantum Fuel Systems (QFS) is the authority in high-quality direct OE replacement fuel system components. All QFS-branded parts are backed by an industry-leading lifetime warranty and are designed to meet or exceed OEM quality. Visit our catalog for all your fuel system needs when maintaining or repairing your fuel pump or fuel system.

1. Keep Your Fuel Tank Full

This is one of the most straightforward tips of the bunch and applies to any standard in-tank fuel pump conveniently located inside your fuel tank. In-tank fuel pumps are constantly submerged in liquid fuel, helping lubricate and cool one of the hardest working components in your fuel system.

Radiant heat from the engine and the fuel pump’s electric motor will increase fuel temperature as your fuel load drops, putting more stress on the fuel pump and causing it to work harder, leading to premature failure.

While today’s gas prices certainly aren’t making things easy for consumers, one of the simplest ways to maintain the health of your fuel pump is never run on empty. Always try to stay above ¼, and your fuel pump will thank you for it. 

2. Don’t Fill Up When The Fuel Delivery Truck Is At The Gas Station

We know that this suggestion might sound like an urban myth, but there is nothing subtle about how a tanker truck dispenses fuel into gas station holding tanks. Thousands of gallons of fuel are dumped into a tank rapidly, stirring up sediment, debris, and even water resting at the bottom.

None of that material is suitable for your fuel system, and it’s best to let the sediment settle before filling up at that station.

3. Inspect Or Replace Filters And Strainers

Filters and strainers are the first and last words in protecting your fuel system. Without them, harmful particulates can mix with a sticky fuel remnant known as gasoline varnish, wreaking havoc on the precision components found in the fuel system and engine. Clogged or damaged filters and strainers can lead to performance loss and premature wear on your internal components.

The first line of defense your fuel system has is a fuel pump strainer that prevents sand, dirt, and foreign objects from clogging or damaging parts. Once a strainer has absorbed all the material it can, it will restrict flow, which puts unnecessary strain on the fuel pump. 

Fuel filters serve the same purpose as a strainer and are typically further up in the fuel system chain. Filters defend engine components, such as your fuel injectors and sensors, from anything that manages to get past the fuel pump strainer.

A clogged filter is detrimental to proper fuel flow, and foreign objects are equally harmful to the rest of your fuel system, clogging small passages and causing performance loss or outright mechanical problems.

Always remember that street-focused motorcycles, cars, and trucks will have much higher service intervals than anything off-road oriented. The harsher off-road environment can quickly introduce dust, dirt, and debris into the fuel system, making maintenance schedules far more frequent on dirt bikes, ATVs, and UTVs/Side-By-Sides.

If you want to maintain your fuel system, stick to regularly servicing the smaller components that you may forget about when doing routine maintenance.

Be sure to reference your model-specific manual for exact mileage/hour figures. Our complete line of filters and strainers are designed to withstand harsh fuel additives and ethanol-based gasoline, ensuring filtration and performance.

ethanol and fuel pumps

4. Clean Your Injectors

Fuel injectors do precisely that: Inject fuel into the engine throttle body or cylinder, allowing a precise amount of atomized fuel to be delivered for proper combustion. Injectors are electronically controlled valves operated by a solenoid that must open and close with extreme accuracy.

Over time, deposits can restrict their spray pattern, causing symptoms like performance loss, decreased fuel economy, rough idle, and misfires. 

Cleaning injectors do not apply to low-mileage/low-hour vehicles unless they’ve sat unused for long periods. Any late model or high-mileage vehicle can benefit from a thorough injector cleaning.

There are plenty of aftermarket tools, solvents, and fuel additives to help clean your injector system. These products remove varnish, build-up, and deposits from small passages, allowing the injector spray pattern to function as intended.

The most effective way to clean any delicate precision component is using ultrasonic cleaning tools. At-home mechanics can purchase specialized tools, but many authorized service shops have the equipment to perform this task.

Ultrasonic cleaning uses high-frequency sound waves transmitted through a liquid to scrub and clean surfaces through a process known as cavitation. These tools are incredibly adept at removing build-up, oils, and other deposits that might obstruct the spray pattern. Ensuring injectors are spraying properly is necessary to maintain your fuel system.

If you find that your injectors are beyond repair, QFS sells direct replacements from reputable brands such as Bosch, Injector Dynamics, RC Engineering, and Siemens Deka. We also stock PnP adapters and wiring harnesses built to fit seamlessly with their respective fuel injector.

5. Maintain Electrical Components

Electrical gremlins are tough, especially when you’re out having fun on your bike, UTV/Side-By-Side, or personal watercraft. Inspecting and double-checking electrical connections is as crucial as changing fluids according to cited service intervals, although many owners don’t make it part of their routine. 

Loose or damaged connectors and wiring can lead to problems beyond intermittent issues. These bad connections could lead to a total failure of a fuel pump, pop fuses or relays, and leave you stranded.

During your routine maintenance, make it a habit to inspect all electrical connections, especially those on off-road oriented vehicles that are subject to running in dirty environments and taking lots of abuse. 

It’s also advisable to test critical electrical systems with a voltage meter to detect problems before they cause harm. While you’re there, hit the electrical connections with some contact cleaner to clean the conductive surfaces.

Lastly, those doing long-distance rides or drives should always look at the most common fuses and relays in their fuse box and carry a spare.

At the most basic level, ensuring your battery is healthy and fully charged is a good place to start. Depending on your charging system, a weak battery can reduce fuel pressure and create lean conditions.

Always keep batteries maintained with a modern “smart charger” that not only maintains a full charge but reconditions your battery and provides a long service life.  

Have Any Questions? Give Quantum Fuel Systems A Call Today!

Quantum Fuel Systems is open Monday through Friday, 8:00 a.m. to 5:00 p.m. PT. We are happy to assist our customers over the phone, or you can browse our extensive catalog. Have any technical questions? Our trained support team will get back to you with answers.

Breaking Down Fuel Pump Terminology: EFI, E85, LPH, Small Parts, and More

Breaking Down Fuel Pump Terminology: EFI, E85, LPH, Small Parts, and More

Navigating the world of fuel systems shouldn’t be difficult, especially when you’re simply trying to order quality parts for your machine. When it comes to fuel pumps, there is quite a bit of common terminology, whether you’re talking about automotive, motorcycle, ATV, UTV/Side-By-Side, or marine vehicles.

We’ve put together a helpful list of standard terms and definitions that you’ll come across when diving into a DIY repair for your vehicle. From basic definitions and acronym explanations — our informative guide will get you on the right path and keep you informed.

Quantum Fuel Systems specializes in producing high-quality fuel system components for nearly every EFI-equipped engine on the market. Our excellent direct replacement parts are designed in-house and will meet or exceed OEM quality. We offer replacement fuel pumps, kits, and components for nearly all makes and models backed by an industry-leading lifetime warranty. Visit our complete catalog to order now.

Fuel Pump Terminology Explained

Electronic Fuel Injection: Electronic Fuel Injection (EFI) is any fuel delivery system that is electronically controlled by an Engine Control Unit (ECU). The name describes its function quite accurately because EFI systems inject fuel directly into an internal combustion engine’s manifold or cylinder. EFI has become the dominant fuel delivery method due to its inherent performance, emissions, and efficiency advantages over antiquated carbureted systems. There are several forms of fuel injection, such as single-point fuel injection, multi-point fuel injection, sequential fuel injection, and direct injection. Yet, they all follow the same fuel injection principles.

Fuel Injector: A fuel injector is one of the most crucial components in your EFI system; its function is where we get the name. A fuel injector is an electronically controlled valve and, when activated by your vehicle’s Engine Control Unit (ECU), sprays a precise amount of atomized fuel into the engine’s combustion chamber to facilitate an optimal air-fuel mixture under all operating conditions. QFS is an authorized dealer of fuel injectors from industry leaders such as Bosch, Injector Dynamics, RC Engineering, and Siemens Deka. We offer direct OE replacement and high-performance solutions for automotive, Powersport, and marine applications.

ECU/ECM: The Engine Control Unit (ECU) or Engine Control Module (ECM) is your vehicle’s brain and controls one or several electrical systems. Part of its duties is managing the EFI system, performing essential tasks like how long to hold the injectors open during each cycle to create the proper air-fuel ratio for any situation. It achieves this by monitoring data from several sensors and adapting accordingly.    

OE Replacement: Original Equipment Replacement. All QFS products for powersports, from fuel pumps, O-rings, and more, match OE specifications and are guaranteed to be direct drop-in replacements. 

OEM: Original Equipment Manufacturer.

Fuel Rail: A fuel rail is a high-pressure fuel line that delivers fuel to the fuel injector.

Fuel Pump Assembly: The fuel pump assembly often houses critical components such as the fuel pump, pressure regulator, fuel sending unit, and strainers or filters. QFS offers entire replacement assemblies for many makes and models. 

Fuel Sending Unit: A fuel sending unit measures the amount of fuel available in your fuel tank and communicates that information to the fuel gauge. It does not send fuel as the name suggests and instead sends an electrical current from the fuel level sensor to the fuel gauge. If your vehicle cannot accurately register fuel levels, a fault with this component can be the cause.

Fuel Pump: Direct OE replacement fuel pumps are what Quantum Fuel Systems specializes in, supporting nearly every corner of the automotive, Powersports, and marine market. The fuel pump delivers high-pressure liquid fuel to a carburetor or EFI system within the engine. All QFS fuel pumps feature an industry-leading lifetime warranty and are designed to withstand a variety of ethanol-gasoline fuel blends. 

Intank Fuel Pump: “Intank” or “in-tank” refers to the physical location of the fuel pump. An intank fuel pump is located inside the fuel tank and explicitly designed for that purpose. Intank fuel pumps typically achieve longer operational lifespans than alternative designs since they are submerged in liquid fuel, helping cool and lubricate the pump.

External/Inline Fuel Pump: External/Inline fuel pumps are mounted on the exterior and underneath a fuel tank, as they use gravity to feed fuel into the pump. An external/inline fuel pump is often far easier to service and replace due to its mounting location. 

Small Parts: This is a term that comes up in conversation with gearheads, sales staff, and suppliers within the fuel-system industry. “Small parts” refers to any components that are not the actual fuel pump. This can include but is not limited to; O-rings, gaskets, strainers, filters, pressure regulators, and other parts associated with fuel pumps. QFS has all the small parts you need to get your vehicle running again. 

Filters: Filters do the critical job of extracting harmful particulates from fuel to protect sensitive EFI components. QFS filters screen microscopic contaminants that collect in a fuel tank and ensure that your vehicle’s EFI system is running at its best. A car, motorcycle, ATV, UTV/Side-by-Side, or boat may employ one or more filters at various stages of the fuel system. 

Strainers: Strainers perform the same function as filters and are typically the first line of defense against fuel system contaminants. Common contaminants such as sand, dirt, dust, and gasoline varnish are screened out by QFS strainers, which feature multi-layer strainer media to filter even the smallest particulates. In addition, QFS strainers boast an expanded surface area, offering improved filtration abilities and extending the life of your fuel system components.

Pressure Regulator: The pressure regulator helps maintain proper PSI within your EFI system, allowing your fuel injectors to function correctly and air-fuel calculations to be as accurate as possible. 

Dual Pump System: Any fuel system that relies on two fuel pumps is a Dual Pump System. In these systems, a low-pressure fuel pump transfers fuel from the fuel tank to the engine, then a high-pressure fuel pump takes over and delivers fuel to the EFI system. These systems are commonly used in marine applications where the fuel tank is not near the engine. 

E85 Fuel (Flex Fuel): E85 is an ethanol-gasoline blend of fuel that can contain anywhere from 51% to 83% ethanol, depending on the season and location. E85, or Flex Fuel, is explicitly formulated for Flexible Fuel Vehicles (FFVs), meaning that the internal combustion engine is designed to support high-volume ethanol fuel blends. While cheaper than gasoline, it has less energy density and often results in reduced fuel economy. This fuel cannot be used in motorcycles and Powersport vehicles.

Tank: The fuel tank. Every ICE-powered machine has one (or more).

Performance: Performance fuel system equipment means that you need components with superior flow rates than what OE equipment can provide. When building high-horsepower engines, this type of equipment is an absolute necessity to meet the increased performance demands.

Polytetrafluoroethylene (PTFE): Polytetrafluoroethylene (PTFE) is a durable synthetic fluoropolymer used in all QFS corrugated flex hose lines. This robust plastic is hydrophobic and resistant to the harsh chemicals in today’s fuels, including E85. The corrugated design also prevents kinking and improves fitment in all uses.

AN Fittings: AN is a U.S. military-derived specification standard dating back to World War II, developed as a common standard between the Army and Navy branches. QFS is an authorized dealer of high-quality AN fittings from Phenix Industries, providing customers with the finest aftermarket high-performance fuel and brake system plumbing components available.

PSI/kPa: Pounds per Square Inch/Kilopascal are two standard measurement units when describing fuel pressure regulator specifications. PSI is an Imperial measurement, and kPa is metric. Be sure to reference what measurement unit your model-specific service manual cites.

LPH/GPH: Liters Per Hour/Gallons Per Hour are two frequently cited units of measurement used to reference the amount of fuel a pump can supply over time. 

Pulse Width Modulation (PWM): Pulse Width Modulation allows an ECU to control EFI fuel pressure by rapidly turning a fuel pump on and off. If more pressure is needed, the length of time the fuel pump is activated extends. Conversely, if less fuel pressure is required, the time the fuel pump is turned on is reduced. This can happen in milliseconds and extends the useful life of a fuel pump by allowing it to work less, operate at a lower temperature, and introduce less heat to the stored fuel. All QFS fuel pumps are PWM-ready.

Done Studying? Reach Out To Our Helpful Staff

Quantum Fuel Systems is open Monday through Friday, 8:00 a.m. to 5:00 p.m. PT. Any of our trained and qualified staff members are available to assist customers over the phone. Be sure to reach out to our support staff with any technical questions, and we’ll get back to you as soon as possible.

Quantum Fuel Systems Releases New Fuel System Solution for LS/LT/EFI Swapped Square Body Trucks

Quantum Fuel Systems Releases New Fuel System Solution for LS/LT/EFI Swapped Square Body Trucks

Ventura, Calif. (April 22, 2022)– Over the last decade, 1973 – 1991 Chevy and GMC C/K pickups, known as “Square Body” trucks, have made a dramatic comeback in the performance and restoration industries. Specifically, LS and Gen V LT swaps have created a trend that has an enormous following in the automotive community.

For years, owners and installers have been sourcing fuel system components from multiple manufacturers to satisfy the higher pressure needs of the LS and LT engines. Enter Quantum Fuel Systems. 

After months of research and development, Quantum has launched the highly anticipated QFS-H880 and QFS-H881 hangers. The H880 boasts 6AN inlet and return fittings designed to facilitate the installation of braided or push-lock type AN hoses without using compression fittings.The H881 features conventional barbed fittings, allowing the use of conventional slip-on style EFI hoses.

Both hangers facilitate the installation of the ACDelco EP381, Walbro/TI Automotive 255LPH, or AEM/Aeromotive/Quantum 340LPH fuel pumps without splicing connectors inside the tank. The Quantum hanger also offers the option to add preinstalled high volume fuel pumps. 

Each hanger comes with two wiring pigtails compatible with the common ACDelco EP381, Walbro/TI Automotive 255LPH, and 340LPH intank pumps. Quantum Fuel Systems assembles each hanger to-order and pre-installs the purchaser’s chosen fuel pump prior to shipping.

All QFS fuel pumps and hangers are covered by Quantum Fuel Systems’ Lifetime Warranty.

Vehicle Compatibility:

1973-1991 Chevrolet & GMC Square Body Trucks with LS/LT Swap

Models: C10 / K10 / R10 / V10 / C20 / K20 / R20 / V20 / C30 / K30 / R30 / V30


  • Coating: Corrosion resistant
  • Check Valves: Integrated check valve built into fuel pump outlet
  • Applications: Can be used on EFI LS or LT swapped Square Body trucks
  • Type: In-tank Fuel Pump Hanger with Sending Unit
  • Wiring: 14 gauge Walbro 255LPH pigtail included. Plug and play adapter harness included for use with AC Delco EP 381 pump
  • Submersible high pressure rubber hose included, compatible with gasoline as well as ethanol based fuels (E85)
  • Serialized fuel pump body guarantees Lifetime Warranty 
  • Various pump and filter options available

To order, click here

For more information, call 818-574-3835, email or visit

A Brief History of the Square Body: 1973-1987 Chevy & GMC C/K Pickup Trucks

A Brief History of the Square Body: 1973-1987 Chevy & GMC C/K Pickup Trucks

When talking about iconic pickup trucks, the conversation will always steer towards one of the most successful lines in truck history. The longstanding Chevy and GMC C/K series that spans over six decades, from 1960 to 2002. But, there is a strong chance that a big part of that debate will focus on the popular third-generation 1973 – 1987 Chevy and GMC C/K models, known as Square Body trucks. 

Square Body refers to the series of C/K trucks that debuted in 1973. They immediately rose to fame, paving the way for an impressive 14 years of continuous production — without any major redesigns. A wide variety of models were offered, including light, medium, and full-sized pickup trucks and SUVs.

Select Square Body models, such as the Blazer, Suburban, and dual-wheel pickups, continued production until 1991. But generally speaking, ’73 – ’87 is seen as the primary years of production for Square Body trucks.

Square Body History

C/K terminology is straightforward, with “C” denoting two-wheel-drive trucks, while “K” signifies four-wheel-drive variants. Meanwhile, the numerals 10, 20, and 30 represent weight class, breaking things down by half-ton, three-quarter-ton, and one-ton, respectively. For example, a C10 model is a two-wheel-drive half-ton pickup.

Interestingly, while the public quickly bestowed the nickname Square Body on the third-generation C/K trucks, it was officially known as the “Round Line” style by Chevy designers. However, compared to prior generations, its boxy body style lent itself to the colloquial name.

It was a radically different design from previous iterations of the C/K line. The new trucks aimed to improve visibility with larger glass areas and curved side windows. In addition, the windshield, door frames, and square wheel wells all feature rounded corners, hence the name “Round Line.” 

What helped propel the Square Body’s popularity focused on creature comforts with more elaborate dashboards and interiors. A far more spacious cab was complimented by cushier seating, increased airflow, better insulation, and weatherproofing, which improved the driving experience.

Four-door crew cab options were also available on select models, making them appeal to wider audiences.

The Square Body also introduced an all-new chassis that offered superior ride quality. Longer wheelbases helped increase stability, while frames featured additional bracing. In addition, staggered rear shock absorbers and leaf spring geometry were revised, to name a few of the changes.

There were a total of five engine choices offered across the C/K range. 250 and 292 inline 6-cylinder engines were common in light-duty trucks, while others used 307, 350, or 454 V8 engines.

Square Body Popularity

Total production numbers for Square Body trucks are difficult to pin down. However, it is estimated that over 10 million units were manufactured, and plenty of fine examples are still on the road today.

Initially, these trucks were incredibly popular with tradespeople due to their robust nature, hauling capability, and variety of powertrain options. Their massive production volume made replacement parts easy to come by and relatively affordable.

In fact, most auto parts suppliers still supply common components for C/K models, despite their age. 

Fast forward a few decades, and the Square Body has moved from the role of a farm or construction workhorse to one of the darlings of the performance truck world. A thriving Square Body community exists where owners lovingly restore hot rod, mud bog, autocross and do anything imaginable to these trucks.

These are simplistic trucks that most home mechanics can build up in their garage, upgrading chassis, brakes, and engine components without serious modification. Combine a vehicle range available in high numbers with massive aftermarket support, and you generally have a winner on your hands.

The massive engine bays of C/K trucks are appealing for those going the performance route. Engine swaps for modern high-performance LS or LT engines are easy to net huge gains in horsepower and torque without too much trouble.

LS / LT Swap Solutions

Of course, if you’re doing an LS or LT swap in your 1973 – 1987 Chevy and GMC / K10 / R10 / C20 / K20 / R20 / C30 / K30 / R30 / V10 / V20 / V30 truck, you’ll want to install our LS/LT Swap Fuel Pump Hanger and Sending Unit. Our brand new 6AN/6AN hanger is a clean-sheet design meant to facilitate the installation of braided AN hoses without adapters and without splicing wires — saving you time, effort, and money.

Every kit comes with two wiring pigtails compatible with AC Delco EP381, Walbro 255LPH, and other 340LPH intake pumps. Quantum pre-assembled fuel pump hangers feature a lifetime warranty on the Quantum fuel pump and sending unit. This is the last hanger your LS/LT swapped Square Body truck will ever need.

There is no doubt that the truck market is seeing renewed interest in the third-generation C/K Square Body trucks. We’re excited to see how a new generation of owners will put their spin on them. For all of your fuel system needs on your C/K truck, be sure to check out our web store. All orders ship the same business day! 


  • Chevy / GMC Square Body series spanned from 1960 to 2002
  • 1973 – 1987 are the primary years of production for Square Body trucks
  • The numerals 10, 20, and 30 represent weight class, breaking things down by half-ton, three-quarter-ton, and one-ton, respectively
  • The Square Body introduced an all-new chassis that offered superior ride quality
  • Square Body has moved from the role of a farm or construction workhorse to one of the darlings of the performance truck world
  • Engine swaps for modern high-performance LS or LT engines are easy to net huge gains in horsepower and torque without too much trouble