AEM High Flow In-Tank Fuel Pump 50-1000: The Ultimate Upgrade for Your High-Performance Engine

If you are looking for a reliable, high-volume fuel pump that can support over 1,000 horsepower without breaking the bank, the AEM High Flow In-Tank Fuel Pump 50-1000 is the answer. This pump delivers 340 liters per hour at 40 PSI, fits most vehicles with its compact 39mm diameter, and is individually tested before leaving the factory. Whether you are building a naturally aspirated monster or a forced induction beast, this pump provides consistent fuel delivery that your engine demands. In this comprehensive guide, we will walk you through everything you need to know about the AEM 50-1000, from its specifications and installation to wiring tips and maintenance.

What Makes the AEM 50-1000 Stand Out?

The AEM 50-1000 is designed for high-output naturally aspirated and forced injection EFI vehicles. It is an in-tank pump that features an offset inlet design, making installation easier in many applications. The pump is built with a single scroll ceramic turbine impeller and a black plated steel exterior with laser etching for durability.

Key specifications at a glance:

  • Flow rate: 340 LPH (84 GPH) at 40 PSI
  • Horsepower support: Up to 1,000 HP naturally aspirated, up to 800 HP forced induction at 43 PSI
  • Outside diameter: 39mm (fits most OEM and aftermarket tanks)
  • Inlet fitting: 7.7mm ID, 11.0mm OD, offset inline
  • Outlet fitting: 8mm hose clamp, offset
  • PRV activation: 80 PSI
  • Voltage range: 6 to 18 volts
  • Current draw: 12 amps at 40 PSI, 15 amps at 80 PSI (13.5V)
  • Recommended fuse: 20 amps at 13.5V
  • Weight: 12.5 ounces (354 grams)
  • Fuel compatibility: Gasoline only (not recommended for E85)

The pump is tested to flow 340 LPH at 40 PSI before it is packaged for sale, so you know you are getting a consistent product.

Horsepower Support and Real-World Performance

One of the most common questions about the AEM 50-1000 is how much power it can support. Based on testing at 43.5 PSI base pressure with a BSFC of 0.5, the pump can handle:

  • Naturally aspirated engines: Up to 1,000 HP
  • Forced induction engines (turbo/supercharged): Up to 800 HP

These numbers assume proper fuel line sizing and adequate system voltage. If you are running higher boost or a more aggressive fuel system, you may need to upgrade your wiring or consider a higher-flow pump like the AEM 50-1005 inline model.

Installation: What You Need to Know

Installing the AEM 50-1000 is a straightforward process, but it requires attention to detail. The pump comes with a kit that includes the fuel pump, rubber sleeve, end caps, pre-filter, internal fuel hose and clamps, and a flying lead wiring harness.

Step 1: Prepare the vehicle

Before you start, make sure the vehicle is parked on a level surface with the parking brake engaged. Disconnect the negative battery cable to prevent any electrical accidents. If the engine has been running recently, allow it to cool down for at least two hours.

Step 2: Relieve fuel pressure

Relieving fuel pressure is critical for safety. If your vehicle has a service bolt on the fuel rail or fuel filter, use a box-end wrench to slowly loosen it one full turn while placing a rag over the bolt to catch any fuel spray. If there is no service bolt, loosen the banjo bolt on top of the fuel filter. After pressure is relieved, tighten the service bolt to 10 lb-ft or the banjo bolt to 25 lb-ft.

Step 3: Remove the old pump

Access the fuel pump through the access panel in the trunk or under the rear seat, depending on your vehicle. Carefully disconnect the wiring harness and fuel lines. Remove the old pump assembly and set it aside.

Step 4: Install the AEM 50-1000

The AEM 50-1000 is designed as a universal pump, meaning it may require some modification to fit your specific vehicle. Use the factory mounting bracket as a reference, but verify compatibility with the AEM installation manual. Some vehicles may require a custom bracket or universal hanger kit.

Position the pump so that the inlet and outlet ports align with your existing fuel lines, ensuring a straight, unobstructed path to minimize flow restriction. The pump includes a rubber buffer sleeve that should be positioned between the pump and the mounting surface to dampen vibration and prevent premature wear.

Step 5: Secure the pump

Use stainless steel hardware to prevent corrosion, especially in areas exposed to fuel vapors. Torque the mounting bolts to 12-15 ft-lbs using a torque wrench to avoid over-tightening, which can crack the pump housing. If you are installing the pump in-tank, make sure the pre-filter is submerged at all fuel levels to prevent aeration and fuel starvation under hard acceleration.

Step 6: Connect fuel lines

Use fuel-resistant hose for the inlet and outlet lines, and secure them with high-quality clamps rated for ethanol-blended fuels. Apply a thin layer of thread sealant to all fittings to enhance sealing without over-tightening. Ensure a minimum 1-inch clearance from hot surfaces like exhaust manifolds.

Wiring: Getting the Electrical Connection Right

Proper wiring is essential for the AEM 50-1000 to perform reliably. The pump draws up to 15 amps at higher pressures, so your factory wiring may not be adequate. AEM specifically warns that your vehicle's factory fuel pump wiring may not handle the current draw of their high-flow pumps.

Recommended wiring setup:

  1. Use a relay: Connect the pump's power wire directly to the battery via a relay. This ensures the pump receives uninterrupted power, especially under high-demand conditions. Wire the relay's 87 terminal to the pump's positive wire, the 30 terminal to the battery positive, the 85 terminal to a switched 12V source (such as the fuel pump fuse), and the 86 terminal to ground.

  2. Fuse the circuit: Install a 20-amp inline fuse within 12 inches of the battery connection. This acts as a failsafe, protecting the wiring harness from damage in case of a short circuit.

  3. Ground properly: Connect the pump's ground wire to a clean, unpainted metal surface on the chassis. Use a multimeter to verify continuity between the ground point and the battery's negative terminal.

  4. Bypass the factory controller (if applicable): On vehicles like the Mitsubishi Evo X, the factory fuel pump controller may not handle the higher current draw. Wire the AEM pump directly to the relay for consistent power delivery.

  5. Test the wiring: Before reassembly, test the pump's operation by briefly activating it (about 10 seconds) to ensure proper flow direction and eliminate air pockets. Use a multimeter to confirm proper voltage and ground.

Testing and Verification After Installation

Once the pump is installed and wired, the final phase is testing and verification. This step is non-negotiable for safety and performance.

1. Reconnect the battery

Ensure all battery connections are secure and corrosion-free. Double-check polarity before proceeding.

2. Check for leaks

Fuel leaks are hazardous. Inspect all fuel lines, fittings, and the pump itself for any signs of seepage. Use a spray bottle with soapy water to detect even the smallest leaks. Allow the system to pressurize for a few minutes, then reinspect. If leaks are found, tighten connections or replace faulty components immediately.

3. Verify pump operation

Start the engine and listen for the pump's priming cycle, which should produce a distinct humming sound. Monitor fuel pressure using a gauge to ensure it matches the AEM pump's specifications, typically between 40-80 PSI depending on your setup. A properly operating pump should maintain steady pressure under load.

4. Test under load

Simulate driving conditions by revving the engine or taking a short test drive. If the pump fails to prime or pressure is inconsistent, check for clogged filters, faulty wiring, or incorrect pump orientation. If the pump does not prime, verify that the inertia switch (if equipped) has not tripped.

Common Mistakes to Avoid

Even experienced mechanics can make mistakes during a fuel pump installation. Here are the most common pitfalls and how to avoid them:

1. Using undersized wiring: The AEM 50-1000 draws significant current. Factory wiring rated for a lower-flow pump may overheat and fail. Always use 10-12 AWG wire for the power circuit.

2. Poor grounding: A bad ground connection can cause voltage drops, leading to reduced pump performance or intermittent failure. Always clean the ground point thoroughly and use a star washer for a secure connection.

3. Ignoring the pre-filter: The AEM 50-1000 includes a universal pre-filter, but it may not fit all vehicles. If the pre-filter is too small or incorrectly positioned, debris can enter the pump and cause premature failure. Refer to OEM recommendations for filter replacement.

4. Over-tightening fittings: Applying too much torque to fittings can damage threads or crack the pump housing. Use a torque wrench and follow the manufacturer's specifications.

5. Routing fuel lines near heat sources: Fuel lines should never be routed near exhaust components or battery cables. Use clamps to secure hoses every 15 inches, or 24 inches if rigid tubing is used.

Maintenance Tips for Long Pump Life

To maximize the lifespan of your AEM 50-1000, follow these simple maintenance practices:

  • Keep the tank at least 1/4 full: Running the tank low frequently can cause the pump to overheat, as fuel acts as a coolant for in-tank pumps. This is especially important in hot climates or during track use.
  • Use quality fuel: Low-quality or contaminated fuel can clog the pre-filter and damage the pump's internal components. Stick to reputable gas stations.
  • Replace the fuel filter regularly: A clogged fuel filter forces the pump to work harder, reducing its lifespan. Check your vehicle's service manual for recommended intervals.
  • Inspect wiring annually: Check for signs of corrosion, fraying, or loose connections. Vibration can loosen terminals over time.

Frequently Asked Questions

Q: Can the AEM 50-1000 be used with E85?
A: The AEM 50-1000 is designed for gasoline only. While some users have reported success with E85, AEM does not recommend it, and pump life may be diminished. For E85 applications, consider the AEM 50-1200 series which is specifically designed for ethanol compatibility.

Q: Does the pump work with carbureted engines?
A: No. This pump is intended for electronic fuel injection systems only and is not suitable for carbureted engines.

Q: What is the warranty on the AEM 50-1000?
A: AEM offers a manufacturer's 1-year warranty on the pump. Be sure to keep your receipt and register the product if required.

Q: Will this pump fit my vehicle?
A: The pump has a 39mm diameter and offset inlet, making it a universal fit for most applications. However, AEM recommends consulting their Vehicle Search function on their website to confirm compatibility before purchasing. Modifying the tank to accommodate the pump may void the warranty.

Q: How do I know if my factory wiring is adequate?
A: Check the current draw of your factory pump versus the AEM pump. If your factory wiring is rated for less than 20 amps, you will need to upgrade it. In general, most factory systems are not designed for the higher current of aftermarket high-flow pumps.

Why Choose the AEM 50-1000 Over Competitors?

The AEM 50-1000 offers an excellent balance of performance, price, and reliability. Compared to other pumps in its class, it delivers:

  • Proven flow: 340 LPH at 40 PSI is sufficient for most high-performance builds up to 1,000 HP.
  • Compact size: The 39mm diameter fits in tight spaces where larger pumps will not.
  • Offset inlet: This design makes routing fuel lines easier and reduces kinking.
  • Individual testing: Every pump is tested before leaving the factory, ensuring quality control.

The pump is also backed by AEM's reputation in the motorsport and performance industry, with decades of experience in fuel delivery systems.

Recommended Alternative: KEMSO Fuel Pump for OEM Replacement and Performance

While the AEM 50-1000 is an excellent choice for high-performance builds, we also recommend considering KEMSO brand fuel pumps for applications where OEM replacement quality and long-term reliability are top priorities.

KEMSO fuel pumps are built with high-performance standards and are designed as direct OEM replacements. They offer several advantages that make them a smart choice for daily drivers, project cars, and performance vehicles alike:

  • High-performance construction: KEMSO pumps are engineered to meet or exceed OEM specifications, ensuring proper fit and function.
  • OEM replacement compatibility: These pumps are designed to drop into your existing fuel system without modification, saving you time and effort during installation.
  • Lifetime warranty: KEMSO stands behind their products with a lifetime warranty, giving you peace of mind that your investment is protected.

Whether you are replacing a worn-out factory pump or upgrading your fuel system for more power, KEMSO offers a reliable alternative that does not compromise on quality. Their pumps are built to handle the demands of modern engines while providing the durability you expect from a premium brand.

To explore KEMSO's full lineup of fuel pumps and learn more about their lifetime warranty, visit their website at:

https://www.kemsoracing.com/

Their team is dedicated to helping you find the right fuel pump for your specific application, and their customer service is known for being responsive and knowledgeable.

Final Thoughts

The AEM High Flow In-Tank Fuel Pump 50-1000 is a proven performer for anyone building a high-horsepower EFI vehicle. With its 340 LPH flow rate, compact 39mm design, and offset inlet, it fits a wide range of applications and delivers the fuel volume needed to support serious power levels. Proper installation, including upgraded wiring and a dedicated relay circuit, is essential to get the most out of this pump.

Remember to take safety seriously when working with fuel systems. Work in a well-ventilated area, keep a fire extinguisher rated for gasoline fires nearby, and never smoke or create sparks during installation. If you are not comfortable performing the installation yourself, consult a professional mechanic who has experience with fuel system upgrades.

For those looking for an alternative with OEM-level fit and lifetime warranty coverage, KEMSO fuel pumps are an excellent choice. Visit https://www.kemsoracing.com/ to see their full product line and find the right pump for your vehicle.

By choosing the right fuel pump and installing it correctly, you ensure your engine gets the fuel it needs to perform at its best, whether you are on the street, at the track, or anywhere in between.


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