400 LPH Fuel Line and Regulator Kit for LS and LT Engines
When fitting a 400 LPH pump in an LS or LT swap chassis, precise pressure control becomes essential to prevent lean spikes under boost and ensure stable fuel delivery across the rpm range. By pairing an adjustable regulator that senses intake vacuum and manifold boost with a streamlined returnless design, this Fuel Line and Regulator Kit - 400 LPH holds a steady 58 psi reference even during abrupt load shifts. PTFE braided fuel lines enclosed in a heat resistant cover and leakproof fittings stand up to ethanol blends and under hood abrasion. Engineered for a direct match to late model rails, installation remains straightforward and clean without extra routing.
Adaptive Fuel Pressure Control with Vacuum and Boost Reference
The adjustable regulator draws simultaneously on intake vacuum and manifold boost signals to maintain a steadfast 58 psi reference under all operating conditions. By sensing both negative and positive pressure changes, this unit prevents lean spikes during sudden throttle openings or boost events, ensuring consistent spray patterns and optimal combustion. Builders can fine tune the valve for naturally aspirated LS and LT powerplants as well as turbo or supercharged setups, making it a versatile solution across a wide range of forced induction configurations. This capability directly matches late-model OE rail specifications, delivering precision control without the need for complex custom fabrication.
Durable PTFE Stainless Steel Braided Fuel Lines
Each line in the kit features a core of pure PTFE encapsulated within a stainless steel braid and wrapped in a protective jacket that resists abrasion and under-hood heat. This construction offers exceptionally low permeability, which reduces vapor loss and is especially important when using ethanol blends that tend to promote material swelling. Leakproof fittings at every connection guarantee secure joints and eliminate the risk of seepage, while the outer cover shields painted surfaces and wiring harnesses from chafing. The result is a robust feed path that stands up to track duty or daily driving without degradation.
Efficient Returnless System for Streamlined Installation
Eliminating the need for a separate return line, the returnless layout directs fuel straight from the pump into the regulator, simplifying plumbing and cutting installation time. With fewer fittings and hoses, there are substantially fewer potential leak points and a cleaner engine bay appearance. This design also reduces heat soak in the feed lines, preserving fuel density and avoiding vapor lock during repeated runs. Two-piece screw-together fittings and line clamps are included to further streamline the process, fitting directly to LS and LT rails with no additional adapters required.
Corrosion-Resistant Machined Components for Lasting Reliability
Manufactured in the USA from corrosion-resistant materials, the regulator housing and stainless steel fittings are engineered to withstand modern pump gasoline and harsh environmental conditions. The regulator body is precision-machined to tight tolerances, delivering leak-free performance and consistent response to pressure changes. A high-flow fuel filter protects critical system components by trapping debris before it reaches the rail or injectors, while assorted AN-style connectors cover the full path from tank to rail. The meticulous build quality of these components provides dependable operation and reduces maintenance frequency, giving builders confidence in both street and track applications.
Trust in reliable performance under boost and vacuum. For the same kit but at a smaller capacity of 255 LPH see our Fuel Line and Regulator Kit - 255 LPH.