LS Swap EFI Sending Unit and In-Tank Pump for G-Body
An LS swap in a G-Body hinges on consistent fuel delivery and precise tank readings, and this EFI Sending Unit and In Tank Fuel Pump assembly addresses both with direct integration into the factory flange. It uses a precision 3/8 inch feed line sender that matches the stock float mechanism and resistance curve for accurate gauge reporting. The integrated Walbro 255 liter per hour pump sustains up to 550 horsepower demands and resists ethanol corrosion to keep pressure steady during high load operation. Mounting directly to GM tanks for Grand National, Monte Carlo, Cutlass and G8 models, it installs with minimal tank shell modifications and requires no adapter plates.
Precision Gauge Calibration with 3/8 Inch Sender
The 3/8 inch feed line sender is meticulously machined to mirror the original G Body float mechanism and resistance curve, preserving the factory gauge cluster's accuracy without calibration. Tight housing tolerances eliminate unwanted movement or vibration that might skew level readings during cornering or under heavy acceleration. Its direct integration with the stock O ring sealing pattern removes extra adapter points, reducing the chance of leaks and preserving the tank's serviceability. By maintaining consistent electrical contact within the sender, drivers get reliable fuel level data every time the ignition is switched on.
Ethanol Resistant Walbro Pump Ensuring Steady Pressure
At its core, the Walbro 255 liter per hour pump sustains fuel delivery for engines up to 550 horsepower, even under sustained load or rapid throttle changes. The pump's efficient impeller design and tight internal clearances promote rapid system refill after shutdown, cutting down cold start cranking time. Constructed with materials that resist ethanol corrosion, it extends service intervals and preserves performance consistency. Maintaining a stable pressure profile helps prevent lean conditions that could stress injectors or engine internals, ensuring predictable response across diverse driving scenarios.
OEM Tank Flange Integration for G Body Models
This sending unit and in tank pump assembly bolts directly to GM G Body tanks for Grand National, Monte Carlo, Cutlass and G8 models, using the original flange and seal interface. Only a handful of pilot holes are needed to secure the assembly, so installers avoid costly welding or custom bracket fabrication. Retaining the stock tank shell and outer lines keeps the factory appearance under the vehicle intact. By leveraging existing mounting locations and hardware, the design simplifies fitment and reduces potential points of failure.
Hassle Free Installation with Minimal Tank Modifications
The assembly's drop in design streamlines the upgrade from carbureted to electronic fuel injection in just a few hours. Reusing original mounting points and O ring seals allows installers to avoid adapter plates or extensive tank shell alterations. Minimal shell drilling preserves structural integrity and prevents fuel vapor leaks. The result is a clean retrofit path that keeps installation complexity low and downtime to a minimum, so G Body enthusiasts can return to the road faster with modern EFI capability.
For a related FLT product choose our Fuel Fitting Kit for G-Body to complete your installation.