Upgrade Your ’88-’98 Chevy OBS: EFI Fuel Tank with Aeromotive 340 Pump

Chris Hamilton October 11, 2024 Feature Stories Tim Katz

Available for all ’88-’98 Chevy OBS Trucks

Upgrading the fuel system in your ’88-’98 Chevy truck can bring significant benefits, especially if you’re running a modern engine swap like this LSX powered OBS. Today, we’re looking at the ’88-’98 OBS EFI tank with an Aeromotive in-tank 340 pump—a must-have upgrade for any serious builder. This tank not only provides a cleaner, more efficient fuel system, but it also offers notable improvements in weight distribution and overall vehicle balance.

This tank holds approximately 22 gallons of fuel and includes a 41001 in-tank EFI assembly with Aeromotive 340 pump.

Our truck currently still has the X crossmember attached to the factory frame, although we will remove it to set the tank higher up for additional clearance.

The ’88-’98 OBS EFI tank from Boyd Welding is constructed from 0.125-inch 5052 aluminum, making it both lightweight and durable. It boasts a capacity of approximately 22 gallons and comes equipped with crucial features such as a 2-inch OD ribbed for hose (RFH) barb-only tank fill, dual ½-inch NPT vents, and a ⅜-inch NPT tank return. The tank also includes a fuel sensor flange and three internal baffles to prevent fuel slosh, ensuring consistent fuel delivery under various driving conditions.

The Boyd Welding tank is designed to mount under the crossmember though, so if you want to leave it in place you can.

To remove the crossmember, Tim shaved down the welds and rivets with an angle grinder and a pair of safety glasses.

One of the standout features of this EFI tank is the integrated Aeromotive 340 pump, known for its reliability and high performance. The pump fitting on the plate is threaded for a -6 ORB fitting (9/16-18 O-ring), making it compatible with a variety of fuel systems. The design of the tank allows it to mount directly to the bottom of the frame rail, eliminating the need to remove the “X” shape rear cross member. However, if you’ve modified your suspension with a 4-link coilover or airbag setup as we did, the tank can be mounted to the top of the frame rail with some additional fabrication.

With the crossmember removed, Tim set the tank in place from the top down. This will make removing it later on a bigger task but the extra clearance makes it worth the work.

Here you can see how much of the tank is extended past the frame rails. With this truck so low to the ground, the higher mounting position was the right call.

The installation process is straightforward, requiring only basic tools and some drilling to fit the mounting tabs. The kit includes all necessary hardware, making it a hassle-free upgrade that can be completed in a few hours. For those who have removed the rear crossmember, be prepared for some additional steps to fabricate mounting points and potentially modify the bed floor to accommodate the tank.

In the following steps, we’ll guide you through the installation process so you get the most out of your new EFI tank. This simple yet effective upgrade will not only enhance the performance of your Chevy truck but also provide a more reliable and efficient fuel delivery system. Let’s go!