Wrist pin Bushing

So what do you drill a hole all the way from the big end to the small end to get oil up there?
 
I would think drilling a stock set of rods would really weaken them. I think you would be better off going to a billet rod with the holes in them . They would be made with better material and be stronger to start with.
 
Toolman said:
I would think drilling a stock set of rods would really weaken them. I think you would be better off going to a billet rod with the holes in them . They would be made with better material and be stronger to start with.
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How big of hole do you need? I would think a very small hole would be what is needed, or to run the Jjet and really squirt the oil in them. What piston was this on?
 
Woodruff billet rods can be ordered with an oiling hole. The downside is the waiting list to get a set. Drew @ D&J Precision can get them ordered for you.
 
hmmm I'd be curious if you could run like a 1/16th hole down or something small from one end to the other.
 
I think think it would be hard to drill them after they have been heat treated even though they aren't that hard. Doing a .06 hole would be like shooting pool with a rope at that length the drill would really want to wander off. . I would probably be looking at maybe an 1/8 hole min. Personally I don't think it would be worth the messing around . If your spinning the motor that hard and making that much power it should have a good set of rods in it.
 
I'd look into the bushing material first, I know my Woodruff's are not just a factory bushing, quite a bit harder.

IMO I couldn't be bothered to put anything but Billet rods in a competition engine.
 
It was on a cast motorsports piston. It was one that did not have the cooling gallery in them. The pistons look great. I measured the pin hole in them and they are the same as when I put them in. What kind of wait am I looking at for the Woodruff's I need to be running by the beginning of march. Sooner if I want some dyno time(and I do).
 
After this years tear down. I once again found all of the rod bushing in all six rods turned, mashed and seized to the wrist pins. They looked indentical to the rods last time. The rods were carillos this year. All pistons looked good, other than were the turned bushing was chewing on them.
 
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Stock wrist pins are your problem. They are flexing causing the damage. Put in tool steel pins and you won't have that issue anymore.


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Were is the best place to get them. It is amazing to think that a 40mm pin can flex in such a short distance.
 
I haven't had the problem before, but the bottom of the pistons have a heat discoloration, and one side of the pins is showing it. Suppose there's still a piston cooling problem?
 
It's possible you have piston cooling problems, but the damage to the rods and pins is from the wrist pins flexing.


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I am using the jets in the main caps. They were clear and in good shape. Should I switch to the j-jets. Could I use both. The engine is pulled cold. Just enough run time to get it to the track and backed to the sled. Oil pressure is always 80-90psi going down the track.
 
That bearing transfer looks like oil issues. I have never heard of the wrist pin flex before. I am sure it's possible but seems unlikely. Whose pistons ?
 
Mahle cast 03-04 style with out gallery cooling. I am sure there was an oil issue after the bushing turned blocking the oil holes. But they started lined up so something is happening.
 
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