NRE 427 LS Naturally Aspirated

Output: 650+ HP on 91 Octane
Configuration: High-compression naturally aspirated LS V8

The NRE 427 LS Naturally Aspirated engine is built for drivers who want strong, reliable power without forced induction. Designed to run on 91-octane fuel anywhere, this package delivers a classic aggressive hot-rod sound, instant throttle response, and a wide usable powerband. With over 650 horsepower and the ability to rev beyond 7,000 RPM, it offers one of the most engaging naturally aspirated LS driving experiences available.

A custom hydraulic roller camshaft eliminates routine valvetrain service, while modern engine management automatically compensates for altitude and driving conditions. This engine is suited for both extended street use and spirited performance driving.

Performance Overview

• Displacement: 427 cubic inches

• Induction: Naturally aspirated

• Fuel Requirement: 91 octane

• Power Output: 650+ HP

• Maximum RPM: 7,000+ RPM

• Engine Management: Laptop-programmable ECU

Engine Specifications

Block & Rotating Assembly

• Block: Dart LS Next, 4.125″ bore, 9.240″ deck

• Crankshaft: Dart billet, 4.0″ stroke

• Connecting Rods: Boostline, 6.125″ length

• Pistons: JE forged, 10.8:1 compression

• Piston Rings: Steel ring set

Valvetrain & Timing

• Camshaft: Custom NRE hydraulic roller

• Lifters: Delphi LS7 hydraulic lifters

• Rocker Arms: Comp Cams shaft rocker system

• Pushrods: Manton Series 5

• Timing Chain: Cloyes Z-Chain

• Timing Cover: GM

Cylinder Heads & Sealing

• Cylinder Heads: NRE AFR 260cc LS3

• Configuration: Six-bolt, fully CNC-ported

• Head Gaskets: Cometic

Induction & Fuel System

• Intake Manifold: Shauns LS3 all-billet intake

• Fuel Injectors: 60 lb/hr

• Engine Management: Holley laptop-programmable ECU

  • Complete wiring harness and sensors included

Lubrication & Hardware

• Oil Pan: Holley 302-3 with high-volume pump and pickup

• Harmonic Damper: ATI

• Valve Covers: NRE billet, fully CNC-machined

• Fasteners: ARP throughout

Key Characteristics

• Strong naturally aspirated power on pump fuel

• High-revving LS platform with immediate throttle response

• No routine valvetrain service required

• ECU adapts automatically to altitude and conditions

• Fully assembled, dyno-tested, installation-ready engine

Typical Applications

• High-performance street cars

• Track-day vehicles

• Restomods and classic muscle builds

• LS engine swaps requiring strong NA output