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ACL Race Series Bearings BMW N55B30 2979cc Inline6 DOHC 4v Turbo, Conrod Bearing, extra oil clearance (0.025mm) 6B1584HX

ACL Race Series Bearings BMW N55B30 2979cc Inline6 DOHC 4v Turbo, Conrod Bearing, extra oil clearance (0.025mm) 6B1584HX

Regular price $279.00 AUD
Regular price Sale price $279.00 AUD
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For over 70 years precision engine bearings have been manufactured in Launceston, Tasmania, Australia.

During this time ACL has been a major OEM supplier to the Australian & International automotive industry, whilst providing an extensive replacement product range for the global aftermarket.

Today ACL produces one of the largest aftermarket range of engine bearings and has a global reputation for robust metallurgy, quality, precision, innovation and performance.

ACL has a long and rich history in motorsport – it is in our DNA. The ACL RACE Series Performance Engine Bearings of today has a strong pedigree in motor racing that traces its roots back to the 1960’s with the manufacture of engine bearings for use in the world conquering Brabham Formula 1.

Further experience in the Australian Supercars Championship, drag racing, speedway, drifting & rally with its range of RACE Series Performance Engine Bearings being the first choice for discerning engine builders the world over.

The ACL RACE Series Performance Engine Bearing offering covers over 200 varied engine applications covering a wide range of performance engine bearings for Australian, American, Japanese, Korean & European applications. The range continues to expand to cover new engine releases.

The company has a high degree of vertical integration encompassing: tooling & product design, bearing strip manufacture, tooling & machine manufacture as well as the complex manufacturing processes & systems required to produce the final product.

ACL's Business Management Systems hold the internationally recognized ISO9001: 2015 Quality Management System, ISO14001: 2015 Environmental Management System & ISO451001: 2018 Occupational Health & Safety Management System certification.

Description: BMW N55B30 2979cc Inline6 DOHC 4v Turbo

Capacity: 2979 CC

Cylinders: 6

Bore Size: 3,3071 in / 84 mm

Stroke: 3,5276 in / 89,6 mm


  • HIGH STRENGTH OVERLAY PLATE with reduced thickness for improved fatigue properties
  • HARDENED STEEL BACKS on all rod bearings to improve the support of the bearing lining and assist with bearing retention in the housing.
  • INCREASED CRUSH for improved bearing retention
  • ELIMINATION OF FLASH PLATING on the back of the bearings to improve heat transfer through the bearings and to maximize the grip between the bearings and its housing.
  • INCREASED ECCENTRICITY to compensate for bore distortion at high rpm and to assist in the formation of hydrodynamic oil films.
  • 3/4 GROOVED MAIN BEARINGS to optimize bearing load carrying surface area and oil flow to the conrod bearings.
  • TIGHT CONSISTENT WALL TOLERANCES to help you maintain consistent clearances.
  • ENLARGED ID CHAMFERS on bearing edges where required to accommodate large fillet radius on performance crankshafts.
  • High performance Trimetal engine bearings
  • Designed to withstand higher RPM conditions
  • High strength overlay plate with reduced thickness for improved fatigue properties
    Specifications for STD size only

    Sizes STD
    Oil Clearance
    Half Type Upper & lower
    Material F781
    Min. Std Shaft Size 49,973 mm / 1.9674 in
    Max. Std Shaft Size 49,993 mm / 1.9682 in
    Min. Std Tunnel Size 53,6 mm / 2.1102 in
    Max. Std Tunnel Size 53,616 mm / 2.1109 in
    Max Wall at Crown 1,78 mm / 0.0701 in
    Max Overall Length
    17,55 mm / 0.6909 in