400 LPH Fuel Line and Regulator Kit for LS and LT Engine Swaps
Whether you are tackling an LS or LT conversion, consistent fuel pressure under boost is critical and the Fuel Line and Regulator Kit - 400 LPH meets that demand from day one. This USA made kit features corrosion resistant materials, a vacuum and boost compensating regulator calibrated to OE 58 psi, and a PTFE braided line with stainless steel sheath and black covering to guard against abrasion or ethanol attack. Two-piece screw together fittings deliver a direct match to LS and LT fuel rails and simplify connections. The returnless layout trims heat soak by shortening feed paths and includes a high flow filter, AN style connectors, and line clamps.
Kit Overview
The Fuel Line and Regulator Kit - 400 LPH is engineered specifically for LS and LT powerplants to deliver precise control over fuel pressure. At its core is an adjustable regulator with a vacuum/boost port that allows fine tuning for both rise and drop in rail pressure according to engine demand. The return-less design enhances rail stability by maintaining constant inlet pressure, eliminating pulsation and reducing the risk of vapor lock under high load scenarios. This configuration supports efficient combustion and consistent power delivery across the entire RPM band.
Material Quality and Performance
Every component in this kit is manufactured in the USA using corrosion-resistant materials chosen for their durability in demanding underhood environments. The PTFE braided fuel line is sheathed in a black protective jacket that resists abrasion, chemical attack, and temperature extremes. This combination ensures long service life and reliable performance even when exposed to engine heat or road debris. The regulator body is treated with a finish that prevents rust and pitting, while internal seals are selected for compatibility with ethanol blends and racing fuels.
Installation and Integration
Installation is straightforward when paired with MuscleRods LS or LT mount systems. The kit's fittings and hose lengths are calibrated to route cleanly alongside motor mounts, exhaust headers, and chassis rails without interference. Using MuscleRods-approved geometry, installers gain optimal engine placement and correct fuel rail angles, ensuring that the vacuum/boost port remains accessible for diagnostic gauges or boost referenced control. This seamless integration reduces fabrication time and maintains proper clearance to chassis components for a hassle-free setup.
For the Same Kit but at a smaller capacity of 255 LPH, see our Fuel Line and Regulator Kit - 255 LPH.