ACL Race Series Rod Bearing Set | 42 mm 4A-GE / 4A-GZE (1986-89 MR2 / 1987-91 Corolla)

ACL Race Series Rod Bearing Set

For 1986–1989 Toyota MR2 AW11 and 1987–1991 Toyota Corolla AE92 coupe equipped with 4A-GE / 4A-GZE engines using the 42 mm crankpin / 45 mm rod-housing interface.

Overview

ACL Race Series rod bearings are a performance-oriented option for a carefully measured 4A-GE or 4A-GZE rebuild. Their tri-metal construction combines hardened steel backing, a copper-based lining and a lead-tin-copper overlay. Standard, extra-clearance, reduced-clearance and crank-undersize choices let the engine builder match the bearings to the actual crankshaft and connecting rods, rather than choosing by model year alone.

Japan-market coverage includes 1986–1989 Supercharged MR2 and 1987–1989 naturally aspirated MR2 with the later 42/45 mm assembly; U.S.-Market MR2 coverage is 1988–1989. Japan-market coverage also includes 1987–1991 Corolla AE92 coupes with 4A-GE and 4A-GZE engines; U.S.-Market Corolla GT-S coupe coverage is 1988–1991. The engine family and measured bearing interface remain essential restrictions.

Key Features

• Race Series construction: Hardened steel backs, a copper-lead-tin lining, nickel barrier and lead-tin-copper overlay.
• Purpose-built bearing geometry: Increased crush and eccentricity, with tightly controlled wall thickness, for performance engine applications.
• Measured-clearance choices: Three nominal-standard crank options and two crank-undersize options, without confusing extra clearance with a reground crankshaft.

Choosing the Correct Bearing Size

Standard clearance is the reference choice. 0.001 in extra clearance provides approximately 0.001 in (0.025 mm) more diametral clearance than the standard version on the same journal. 0.025 mm reduced clearance provides approximately 0.025 mm (0.001 in) less clearance than the standard version on the same journal. These are selection differences, not guaranteed finished oil-clearance values.

0.25 mm crank undersize and 0.50 mm crank undersize are for the corresponding reground crankpin family. They are not extra-clearance options for an unground standard crank and do not repair an oversized rod housing. The correct choice depends on the finished crankpin diameter, rod housing, bearing geometry and measured assembled oil clearance. Do not substitute one size for another.

Vehicle Fitment

Every application below requires the original-style 42 mm crankpin / 45 mm rod-housing interface and the correctly selected bearing size. U.S. dates are model years; Japan-market dates describe production coverage.

Toyota MR2 — AW11 / MK1

• 1987–1989: JDM / naturally aspirated 4A-GE with the later 42/45 mm assembly introduced at the September 1987 production change. September transition builds require actual crank/rod identification, not the month alone.
• 1988–1989: U.S.-Market / naturally aspirated 4A-GE
• 1986–1989: JDM Supercharged / 4A-GZE
• 1988–1989: Supercharged (U.S.-Market) / 4A-GZE

Toyota Corolla / Sprinter — AE92 — Coupe

• 1987–1991: Corolla Levin / Sprinter Trueno (Japan-market) / 4A-GE 16-valve
• 1987–1991: Corolla Levin / Sprinter Trueno GT-Z (Japan-market) / 4A-GZE
• 1988–1991: GT-S coupe (U.S.-Market) / 4A-GE

Fitment Notes

• Not for original 40 mm crankpin / 43 mm rod-housing assemblies, including original AE86 4A-GE and early naturally aspirated AW11 engines of that size. Original 4A-C, 4A-F and 4A-FE assemblies are not covered.
• A swap, replacement crankshaft or aftermarket rod does not establish compatibility by chassis or nominal diameter alone. Bearing seats, locating tabs, axial width, crank fillets and assembled clearance must match the supported configuration.
• Toyota numbered selective bearing grades do not directly map to these ACL options. No universal oil-clearance or machining target is implied.
• The listed factory applications use 16-valve engines. 20-valve engine applications are not covered.

Product Specifications

Bearing Position: Connecting-rod big end
Construction: Race Series tri-metal with hardened steel backing
Nominal Crankpin Family: 42 mm
Standard Crankpin Reference: 41.985–42.000 mm
Bare Rod-Housing Reference: 45.000–45.024 mm
Maximum Shell Axial Length: 17.10 mm
Shell Design: Identical upper and lower halves

Rod Bearings and Main Bearings

Rod bearings support the connecting rods on the crankpins; main bearings support the crankshaft in the engine block. ACL Race Series standard-size main bearings are a separate, complementary product for a compatible standard-size main-journal assembly. Selecting a rod-bearing undersize does not determine the main-bearing size.

Available Configurations

Choose one bearing size. Every option includes eight rod-bearing half-shells, enough for four connecting rods. Main bearings, thrust washers, connecting rods, piston-pin bushes and gaskets are not included.

Bearing Size

• Standard clearance
• 0.001 in extra clearance
• 0.025 mm reduced clearance
• 0.25 mm crank undersize
• 0.50 mm crank undersize