I need to know if the cam bearings need to be for a grooved cam or one with holes for oiling for Isky RPM300 or E4 applications.

Thanks

Paul J. - '57 E Code

The Isky camshafts are being supplied with a grooved center journal.

 

If the center cam bearing hole in the block is machined with a groove so that all three holes are interconnected behind the cam bearing, the cam bearing design being used will not make a difference regardless of which cam is being used.  You just have to make sure that one of the holes in the bearing is aligned with any of the holes in the block to insure that the cam journal itself get oil.  This alleviates the risk of the groove in the camshaft being too shallow and/or the bearing material being too soft eventually cutting off oil flow to the upper end.

Lorena, Texas (South of Waco)

Interesting question to ponder: A very experienced engine mechanic (heavy equipment) I met recently, said that too much oil pressure will increase cam-bearing wear. Is this likely? You would think very expensive heavy equipment (CAT, etc.) would get frequent oil/filter changes, whereas the abrasive dirt in old oil would seem much more likely to produce excessive wear? I'm puzzled, unless dusty construction environments overcome ANY filtration?

6 VOLTS/POS. GRD. NW INDIANA

Ted's advice about the oil holes in the cam bearing being in alingn with the block is critical.  My engine was just professionally rebuilt and the builder showed me how little opening there really was for the oil to get through the passage in the block and the bearing.   Many of the oil passages in the blocks are not perfectly aligned because the drill will lead off and not come out where it was exactly intended.   A drill must then be run through the passages and the cam bearing redrilled to create a full size oil passage through the bearing and to the cam.   Easy to do and also very easy to over look and be a potential source for problems later on.   J

It would have to be a special set of circumstances in which high pressure oiling would aggravate cam bearing wear and those characteristics are not present on the Y.  But now that we’re talking pressure, the cam bearing modification in the center journal hole doesn’t increase the oil pressure to the top end but merely increases the volume of oil.  If the top end doesn’t have a restrictor installed at the rocker arms, there will actually be a slight drop in overall pressure due to the increase in flow.

Lorena, Texas (South of Waco)