ACL 5M1219H-.25 Race Main Bearing Set +0.25mm Mitsubishi 4G63T 4G64 EVO DSM

Vehicle Fitment

• 1997-2006 Mitsubishi Eclipse GST / GSX (4G63T, 2.0L DOHC 16v Turbo, 2G DSM)
• 1997-2001 Eagle Talon TSi AWD / FWD (4G63T, 2.0L DOHC 16v Turbo)
• 2003-2005 Mitsubishi Lancer Evolution VIII (4G63T, 2.0L DOHC 16v Turbo)
• 2005-2006 Mitsubishi Lancer Evolution IX / IX MR (4G63T, 2.0L DOHC 16v Turbo)
• 1997-2003 Mitsubishi Galant (4G64, 2.4L SOHC 16v)
• Various Hyundai / Kia applications using the 4G64 2.4L engine

Fitment Notes

• This set is specifically for the 1997-on 4G63/4G63T/4G64 "7-bolt" block equipped with separate thrust washers (T/W). The pre-1997 4G63/4G64 uses a flanged main bearing design without separate thrust washers - those engines require 5M1186H instead. Using the wrong main bearing set will result in incorrect fit and clearance.
• The .25 suffix designates this as the +0.25mm oversize bearing set - for use when the crankshaft main journals have been ground 0.25mm undersize. This is the more significant regrind step, typically required when journals have suffered deeper wear or surface damage. For standard journal diameter, use 5M1219H-STD. For crankpins ground 0.025mm undersize, use 5M1219H-.025.
• Thrust washers (1T1219-STD) are sold separately - they are not included in this set. Confirm thrust washer availability before grinding the crankshaft.
• Always measure crankshaft main journal diameter with a micrometer before selecting bearing size. Confirm actual clearance with Plastigage or a dial bore gauge after assembly.
• Sold as a complete set of 10 bearing shells (5 pairs, upper and lower) - sufficient for all 5 main journal positions in one 4-cylinder engine.

Features

• Tri-metal construction: copper-lead alloy lining bonded over a hardened steel backing, with a high-strength overlay plate - engineered for the sustained high-boost loads and high-RPM demands of built 4G63T and 4G64 engines.
• Hardened steel backing on all main bearings improves structural support of the bearing lining and maintains crush under the elevated crank loads associated with high-power 4G63T builds.
• High-strength overlay plate with reduced thickness provides improved fatigue resistance compared to OEM-spec bearings - critical in high-boost DSM and Evo builds running elevated cylinder pressures over extended use.
• Increased bearing crush and tighter wall tolerances ensure consistent, secure seating in the block main journal bores, reducing the risk of bearing movement.
• Enlarged ID chamfers on bearing edges accommodate the larger fillet radii found on performance and aftermarket Mitsubishi crankshafts.
• 3/4-groove upper main bearings optimize oil supply to the main journals and to the connecting rod bearings through the cross-drilled crankshaft oiling passages.
• Elimination of flash plating on bearing backs improves heat transfer and maximizes grip between the bearing shell and the block main bore.
• Increased eccentricity compensates for bore distortion at high RPM and assists in the formation of a stable hydrodynamic oil film under load.

Specifications

• Part Number: 5M1219H-.25
• Product Line: ACL Race Series
• Application: Crankshaft Main Bearings
• Engine Compatibility: Mitsubishi 4G63 (2.0L DOHC), 4G63T (2.0L DOHC Turbo), 4G64 (2.4L SOHC) - 1997-on with thrust washers (7-bolt block)
• Crankshaft Size: +0.25mm Oversize (for main journals ground 0.25mm undersize)
• Shaft (Main Journal) Diameter: 56.735-56.750mm (2.2336-2.2342 in)
• Tunnel (Housing Bore): 61.000-61.021mm (2.4016-2.4024 in)
• Maximum Wall Thickness at Crown: approx. 2.115mm (0.0833 in)
• Maximum Overall Length: 20.63mm (0.812 in)
• Bearing Material: Tri-Metal Copper-Lead Alloy / Hardened Steel Backing
• Thrust Washers: Not Included - order 1T1219-STD separately
• Quantity: Set of 10 Shells - 5 Upper + 5 Lower (complete engine set)

Included Components

• 10x Race Series Crankshaft Main Bearing Shells - +0.25mm Oversize (5 upper, 5 lower)

Product Description

The ACL Race Series 5M1219H-.25 crankshaft main bearing set is the +0.25mm oversize option for the Mitsubishi 4G63, 4G63T, and 4G64 engines in their 1997-on "7-bolt" configuration - the block design used in the 2nd-gen DSM Eclipse GST/GSX, Eagle Talon TSi, and the Lancer Evolution VIII and IX. This oversize set is selected when the crankshaft main journals have been ground 0.25mm undersize - a more significant material removal step typically required when journals have suffered deeper wear or surface damage requiring more than the .025mm regrind step can address.

The 1997+ block is distinguished from the earlier 4G63/4G64 by its use of separate thrust washers at the rear main journal - a critical fitment detail, as the pre-1997 flange-type main bearing (5M1186H) is not interchangeable. Built on ACL's Race Series tri-metal platform, these main bearings deliver superior fatigue resistance and oil film stability over OEM Mitsubishi shells - an important upgrade for any high-power 4G63T build. Thrust washers (1T1219-STD) must be ordered separately. Always confirm clearances at assembly. Sold as a complete set of 10 shells for one engine.