Aftermarket Conrod Oil Hole???

[the phantom]

Why is it that no aftermarket conrod I've seen has the oil squirt hole in the big end for cylinder wall lubrication? I find it strange that the factory insists on doing this if its not really that important. Any ideas?

[proengines]

A lot of aftermarket conrods run more side clearance on the crank journal and there is oil passed through there which splashes onto the bore. The original squirters are there to increase the life of the piston and bore by lubricating the thrust face, many engines get by using only splashed oil for the same purpose.

I would say the main reason the squirter is not drilled is to keep the strength in the rod. A hole drilled through the rod has tiny flaws where cracks can begin.

I think it's more important to keep oil flowing out the sides of the rods and fresh oil being pumped in as the oil stays cooler. The pistons get plenty of splashed oil, plus what comes from the piston cooling jets in most modern engines.

[Chris Wilson]

Stock cast pistons run a tight piston to bore clearance and are expected to be quiet even straight after a cold start. Because of the tight clearance and the need for silence stock set ups usually squirt oil on the bores thrust face to aid cooling and keep a quietening heavy oil film there. You can lightly groove the big end side faces of the rods with a small rat tail file to add more splash if you really want. I wouldn't bother. With a wet sump their is a maelstrom of oil splash anyway...