ACL bearings are used for tuning and engine upgrades where you want better quality with higher bearing capacity than normal standard bearings. Improvements of material, dynamic thickness, heat conduction, oil grooves and oil distribution are some of the points that make ACL one of the leading bearing manufacturers. Bearing data Part number: 6B1490H Bearing size: .25 Bearing half type: Identical halves Bearing material: F781 Technical data (mm) Max overall length: 18 Max shaft size: 44.991 Max tunnel size: 48.016 Max vertical oil clearance: 0.077 Max wall at crown: 1.49 Min shaft size: 44.975 Min tunnel size: 48 Min vertical oil clearance: 0.029 Technical data (in) Max overall length: 0.7087 Max shaft size: 1.7713 Max tunnel size: 1.8904 Max vertical oil clearance: 0.003 Max wall at crown: 0.0587 Min shaft size: 1.7707 Min tunnel size: 1.8898 Min vertical oil clearance: 0.0011 Engine code M20B20 / M20B23 / M20B25 / M20B27 / M50B20 / M50B20TU / M50B25 / M50B25TU / M52B20 / M52B20TU / M52