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Has anyone ever considered cutting a small slot in on the piston side of the cam follower bore. Say a 6-7mm diam cutter and machine a 1mm deep concave slot. The idea being that the windage from the cam will drag the oil that runs down the slot under the cam follower. What do you think.
 

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Has anyone ever considered cutting a small slot in on the piston side of the cam follower bore. Say a 6-7mm diam cutter and machine a 1mm deep concave slot. The idea being that the windage from the cam will drag the oil that runs down the slot under the cam follower. What do you think.
Do you think more oil will lessen lobe wear or is the wear related to cam design and materials?

George Dill
 

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There's more oil flying around the crankcase than you'd ever get to dribble past a new gravity-fed slot. and the slot would interfere with the rotation of the lifter/follower. So no, it doesn't seem like a good idea, to me anyway.

Is your cam worn? Usually only the #1 lobe has much of an issue, and that's generally metallurgy - the legend goes that the cam was oil-quenched vertically, with that end getting dunked last, and therefore least. You can have the lobe built back up with weld, then reground.

If the whole cam is wearing, then check your oil pump and the oil galleries. And the main bearings, too. :)
 

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Hi George,
Articles I have read about oils, talk about the changes in oil wear properties with the high volume of overheads cam engines on the market and the bath of oil around the cam lobe run in has meant oil manufacturers have removed some of the wear inhibitors from the oil.
 

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Thank you for the reply, please read my reply to George, I am building a new engine with increased lift and 1.6:1 rockers and just trying to improve the lobe wear. Steve
 

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Not sure if your idea will make things better or worse but keep in mind that when you open up or add oil passages, you will reduce overall oil pressure. I'm not sure by how much or if it will be enough to cause an issue. Generally a reduction in oil pressure is a bad thing.
 

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Thank you for the reply, please read my reply to George, I am building a new engine with increased lift and 1.6:1 rockers and just trying to improve the lobe wear. Steve
If you do the groove consider a heavy-duty oil pump with stronger spring and reinforced collar.

George Dill
 

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When I pulled my B20E engine apart (with 100,000+ miles), the cam followers had pitting on the bearing surface. It was almost as if the surface of the follower looked like it had become work hardened and was becoming brittle and fracturing. It was not what I would characterize as wear due to a lack of lubrication. It looked more like a metallurgy issue. As a note, my recollection is that all of the lifters had this problem, not just the #1 lifter and cam lobe. The accepted antidote seems to be replacement with Isky lifters rather than OEM lifters.

I think the reduction (not elimination) in the wear additives, primarily zinc, that you refer to has more to do with emission requirements than the prevalence of OHC engines. I think zinc might have an adverse effect on catalytic converters and / or O2 sensors when some of the oil eventually works it way into the combustion chamber. As a side note, none of the OHC engines I have or had have the cam(s) running in an oil bath. The buckets or followers get oil sprayed on the wear surface.
 
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