1965-1966 Chevy Impala and Caprice LS EFI Fuel Tank Kit
When fitting an LS engine into a 1965 to 1966 Chevy Impala or Caprice B Body chassis, finding a fuel system that preserves the factory underbody profile while meeting high horsepower demands often proves tricky. This EFI tank kit places a 400 LPH Walbro pump inside the stock cavity and aligns with OEM mounting points to eliminate extra brackets or modifications. By matching the original steel tank cavity and using ethanol resistant internals, the assembly maintains corrosion protection and delivers consistent pressure under spirited acceleration and sustained cornering. Installation hardware includes precision gaskets and straps to cut bench time and secure a direct fit.
Precision Alignment within the Original Tank Cavity
The fuel module is engineered to nest seamlessly inside the stock cavity of 1965 and 1966 Impala and Caprice B Body frames, matching Chevrolet's original geometry and mounting points. By fitting directly without additional brackets or modifications, it preserves the factory underbody profile and maintains the corrosion protection of the sheet metal shell. Positioning the pump assembly at the correct depth ensures reliable fuel pickup even during hard braking, spirited cornering, or sustained acceleration. Installers benefit from clear alignment cues and precision fit components that reduce trial and error. This direct fit approach also safeguards the classic undercarriage appearance and protects resale value by leaving the original tank welds undisturbed.
Steady Fuel Flow from the 400 LPH Walbro Pump
At the heart of this kit is a proven 400 liter per hour Walbro pump calibrated for high output LS conversions exceeding 550 horsepower. Its rotor and stator design maintain a narrow pressure band, simplifying regulator adjustment and delivering consistent rail pressure from idle to full throttle. The ethanol resistant internals stand up to modern fuel blends, ensuring long service life even under high rpm or boost conditions. This reliable flow rate prevents lean spikes and potential detonations during aggressive driving or track use. Compact dimensions allow the pump to remain fully submerged in fuel, reducing noise and improving efficiency under all load conditions.
Complete Kit Components for Hassle Free Installation
This comprehensive EFI fuel tank kit arrives ready to install with every critical part included, eliminating trips to multiple suppliers. A matched sending unit preserves accurate fuel gauge readings while a replacement filler neck mirrors the factory style for seamless appearance. Precision gaskets and tank straps are sized to the original shell, and zinc plated hardware resists corrosion under the chassis. A dedicated vent filter keeps airborne debris out of the tank, protecting the pump and regulators. These components work together to slash bench time and deliver a professional quality installation that fits like GM engineered it.
Preserving Classic Underbody Styling with Modern Durability
Combining modern performance with vintage sheet metal contours, the module sits entirely within the existing cavity so the surrounding steel and factory paint remain untouched. Heavy gauge materials in the assembly resist vibration and chassis flex common to powerful street machines. The low profile layout maintains original ride height and ground clearance, preserving the Impala's showroom stance beneath the car. By avoiding alterations to the frame rails and floor pan, the kit ensures long term corrosion protection and visual authenticity. This balance of classic styling and robust construction gives high output LS swaps the reliability they demand without compromising period correct appearance.
This MuscleRods EFI tank kit delivers precise fuel delivery and preserves the Impala's original underbody styling. For a smaller capacity fuel pump kit at 255 LPH see our 1965-1966 Impala EFI Fuel Tank Kit - 255 LPH Pump.