ACL Race main bearings for Chevrolet LS and LQ series V8 engines with standard crankshaft and extra oil clearance. The HX version has approximately 0.001" extra clearance compared to the regular H-STD version and is typically used for performance engine builds, tuning and motorsport where slightly greater oil clearance is required under high load.
ACL Race Series is developed for high-load engines where greater demands are placed on the bearings than in regular standard use. The main bearings are manufactured with high-strength materials and an optimised bearing design to ensure high load capacity, improved heat transfer and stable oil supply under load.
The bearings feature extended oil grooves, which help improve oil distribution to the connecting rod bearings and help maintain a stable oil film at high loads and engine speeds. The extra oil clearance in the HX version can be relevant for engines with higher operating temperatures, higher oil pressure, heavier load or specific requirements from the engine builder.
Improvements in material, dynamic thickness, heat transfer, oil grooves and oil distribution are some of the factors that make ACL one of the leading manufacturers of performance engine bearings. Correct bearing fitment and oil clearance must always be checked during installation.
Specifications:
Type: ACL Race main bearings
Material: Trimetal copper/lead alloy (F780) with steel backing and electroplated overlay
Crankshaft: Standard size (STD)
Oil clearance: 0.068–0.084 millimetres
Bearing design: 180° oil groove in the upper bearing half with matching partial oil groove in the lower half
Bearing type: Upper and lower main bearings
Contents: 10 bearing halves (5 complete main bearings)
ACL part number: 5M7298HX-STD
Maximum total length: 26.1 millimetres
Maximum shaft size: 65.007 millimetres
Maximum tunnel size: 69.887 millimetres
Maximum vertical oil clearance: 0.071 millimetres
Maximum wall at crown: 2.42 millimetres
Minimum shaft size: 64.993 millimetres
Minimum tunnel size: 69.873 millimetres
Minimum vertical oil clearance: 0.031 millimetres
Fits engine code:
LR4 / LY2 / LS1 / LS6 / LS2 / LS3 / L99 / LFA / L76 / L98 / Vortec 6.0L / Vortec 6.2L
