Manley 14024-4 H-Beam Connecting Rods ARP Subaru EJ20 EJ25 WRX STI 5.137in 4340

Vehicle Fitment

• 2002-2014 Subaru Impreza WRX (EJ205, 2.0L DOHC Turbo)
• 2004-2021 Subaru WRX STI (EJ257, 2.5L DOHC Turbo)
• 2004-2013 Subaru Forester XT (EJ255, 2.5L DOHC Turbo) - see EJ255 piston note in Fitment Notes
• 2005-2012 Subaru Legacy GT (EJ255, 2.5L DOHC Turbo) - see EJ255 piston note in Fitment Notes
• Compatible with EJ207 (JDM) applications sharing the same rod journal and pin dimensions

Fitment Notes

• WARNING: EJ255 ENGINES (Forester XT, Legacy GT): These rods are compatible with EJ255 engines ONLY when paired with aftermarket pistons that do NOT require a tapered connecting rod small end. OEM EJ255 pistons use a tapered wrist pin bore that is incompatible with the straight small end bore of these H-Beam rods - using OEM EJ255 pistons with these rods will result in improper fitment and engine damage
• Fits EJ205 and EJ257 engines directly with standard wrist pin dimensions - no special piston requirement
• Wrist pin diameter is 23mm (0.905 in.) - verify aftermarket piston pin bore compatibility before pairing with custom piston kits
• Rod bolt torque specification: 60 ft-lbs with 30wt oil; rod bolt stretch: 0.0058 in.-0.0062 in.
• Sold as a set of 4 rods
• Professional engine builder installation strongly recommended

Features

• H-Beam Economical Series - delivers the same forged 4340 construction, machining standards, and quality control as Manley's Pro Series rods at a more accessible price point
• Manufactured from premium forged 4340 chromoly steel alloy for maximum tensile strength and fatigue resistance under sustained high-boost and high-RPM operation
• Rated to approximately 600 crank horsepower - suitable for street rebuilds, daily-driven turbo builds, and moderate competition applications
• Full heat treatment, stress relieving, shot peening, and 100% individual magnafluxing applied to every rod for proven structural integrity and defect-free quality assurance
• Big end and wrist pin bores final honed to ±0.0002 in. tolerance for precision fit and consistent clearance across all four rods
• Bronze alloy small end bushing pressed into the wrist pin bore for improved wear resistance and long-term durability under high-load operation
• Weight matched as a set to within ±1.5 grams for superior rotating assembly balance and reduced vibration
• Critical bend and twist specifications tightly controlled throughout machining and final inspection
• Perfectly round big and small end bores verified through final inspection department
• Includes ARP 2000 3/8 in. cap screws - high-strength performance rod bolts delivering 220,000 PSI tensile strength for reliable clamping at high engine loads
• Manufactured to the same exacting standards developed and approved by Manley's original equipment customers

Specifications

• Rod Style: H-Beam
• Series: H-Beam Economical
• Material: Forged 4340 Chromoly Steel Alloy
• Center-to-Center Length: 5.137 in. (130.48 mm)
• Big End Bore Diameter: 2.165 in. (54.991 mm)
• Big End Width: 0.840 in. (21.336 mm)
• Wrist Pin Diameter: 0.905 in. (23mm)
• Pin Bore Diameter: 0.9063 in.
• Small End Bushing: Bronze Alloy (Pressed In)
• Bore Tolerance: ±0.0002 in. (big end and pin bore)
• Rod Weight: ~535 grams each
• Weight Matching Tolerance: ±1.5 grams per set
• Bolt Size: 3/8 in.
• Included Bolts: ARP 2000 Cap Screws (3/8 in.)
• Rod Bolt Torque Spec: 60 ft-lbs (with 30wt oil)
• Rod Bolt Stretch Spec: 0.0058 in.-0.0062 in.
• HP Rating: ~600 HP (crank)
• Quantity: Set of 4
• Application: Subaru EJ-Series (EJ205, EJ255*, EJ257, EJ207)

Included Components

• 4x Manley H-Beam connecting rods (forged 4340 steel, bronze bushed small end)
• 4x ARP 2000 3/8 in. cap screws (rod bolts)
• 1x Manley assembly lube

Product Description

The Manley 14024-4 is a set of four H-Beam connecting rods engineered for Subaru EJ-series engines, covering the EJ205 (WRX 2.0L), EJ257 (STI 2.5L), and EJ255 (Forester XT / Legacy GT 2.5L, with piston caveat) applications. Machined from forged 4340 chromoly steel alloy and processed through full heat treatment, stress relieving, shot peening, and 100% individual magnafluxing, these rods are manufactured to the same exacting standards Manley applies to its OEM and professional motorsport connecting rod programs. The H-Beam Economical Series designation delivers Manley Pro Series-level quality - precise tolerances, perfect round bores, controlled bend and twist - at a price point accessible to street builders and budget-conscious performance enthusiasts.

Each rod set is weight-matched to within ±1.5 grams for optimized rotating assembly balance, with big end and pin bores honed to ±0.0002 in. tolerance. The pressed bronze alloy small end bushing provides superior wrist pin wear resistance under high-load conditions. At 5.137 inches center-to-center with a 23mm wrist pin diameter, these rods are a direct replacement for EJ205 and EJ257 applications and are rated to approximately 600 crank horsepower - suitable for street builds to moderate competition builds. ARP 2000 3/8 in. cap screws are included; rod bolt torque spec is 60 ft-lbs with 30wt oil, with a target stretch of 0.0058-0.0062 in.

An important fitment caveat applies to EJ255 engines found in the Forester XT and Legacy GT: the OEM EJ255 pistons use a tapered wrist pin bore that is mechanically incompatible with the straight small end bore of these H-Beam rods. These rods can be used in EJ255 engines only when paired with aftermarket pistons that use a straight (non-tapered) pin bore. Using OEM EJ255 pistons with these rods will result in improper fitment and risk of catastrophic engine failure. Builders working with EJ255 applications should confirm piston compatibility with their engine builder before ordering. Professional installation by an experienced Subaru engine builder is strongly recommended.