ACL RACE Series bearing sets are identified by the ‘H’ after the set number e.g. 8B663H-Std. Most ACL RACE Series bearings are also produced in a ‘HX’ version e.g. 8B663HX-Std. The ‘X’ signifies the set will give an extra .001” (.025mm) oil clearance on a standard size shaft when compared to the H-STD set. The wall size of these HX-STD bearings is .0005” (.013mm) thinner than the H-STD Bearings, in all other respects the HX set is identical to the H-STD set. There are selected con rod bearing sets that are manufactured with a dowel hole in the lower shell, to suit a dowel location in the con rod cap. These are designated with a ‘D’ in the set numbering e.g. 8B663HD-Std or 8B663HXD-Std etc.

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