rod bearing question
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rod bearing question
I'm using some hi po Carillo rods in an alfa race engine build. The rods don't have oil spray holes. The bearings I have for these rods have holes for use with OEM style rods.
Given I can't find the right bearings without oil holes, can anyone see an issue using them with the said rods.
I'm thinking if anything they may lube a little better since the hole in the bearing will hold a little extra oil....on the flip side maybe the holes in the bearings will act as a weak point and start peeling metal from their edge.
Thoughts please.
Given I can't find the right bearings without oil holes, can anyone see an issue using them with the said rods.
I'm thinking if anything they may lube a little better since the hole in the bearing will hold a little extra oil....on the flip side maybe the holes in the bearings will act as a weak point and start peeling metal from their edge.
Thoughts please.
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Re: rod bearing question
Any void in a rod bearing, even the tang, gives a place for the hydrodynamic wedge to escape to. Not best case for sure, but if that is the only bearing offered, it is what it is.
Re: rod bearing question
Just so the oil pressure can't get to the backside of the bearing shell and push it out from the rod somehow. I doubt there is enough cross sectional area in the hole to accomplish this though
Re: rod bearing question
Whose bearings do you have? Which Alfa? King is now making bearings for the 101, 105 and 115 series engines.
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Re: rod bearing question
Are these the rods with recalcitrant bolts?
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Re: rod bearing question
OK. I see king's have them listed for the 105 series. But not sure if they too have oil holes. I'll email them.
These are another rod for another engine Kevin. I finally did shift those old bolts. They were fiat twin cam rods. I think I'll have the same issue finding bearings without holes for those too, hence my question.
These are another rod for another engine Kevin. I finally did shift those old bolts. They were fiat twin cam rods. I think I'll have the same issue finding bearings without holes for those too, hence my question.
Re: rod bearing question
OK. Bought some king bearings without holes.
Can anyone still answer the original question though, cause I can't get them for the Fiat build.
Can anyone still answer the original question though, cause I can't get them for the Fiat build.
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Re: rod bearing question
As said in my first post, any void in the bearing face isn't a good thing, but weather it will be detrimental depends on how hard things are pushed. At some level of rpm and oil flow, it can cause a failure. Hard to know if you are operating at or near this limit without experience and post inspection.AC sports wrote:OK. Bought some king bearings without holes.
Can anyone still answer the original question though, cause I can't get them for the Fiat build.
If no other bearings are offered, it is what it is.
Re: rod bearing question
Fair enough. Makes sense. And I can envisage long term the bearing metal beginning to peel around the blind hole.
Hopefully someone can chime in that's had some experience running them as such to provide some real world feedback.
Hopefully someone can chime in that's had some experience running them as such to provide some real world feedback.
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Re: rod bearing question
Porsche 924 Turbo 2.0 ran them and it was critical that they were present rather than what you are asking -- but I agree with Jay that it is not a great idea for the pressure gradient.
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Re: rod bearing question
Do you mean the holes improved performance?Kevin Johnson wrote:Porsche 924 Turbo 2.0 ran them and it was critical that they were present rather than what you are asking -- but I agree with Jay that it is not a great idea for the pressure gradient.
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Re: rod bearing question
Well, when people put bearings in without the oil squirter hole being present the pistons overheated. The Audi block was used in a van of some sort as well.4sfed wrote:Do you mean the holes improved performance?Kevin Johnson wrote:Porsche 924 Turbo 2.0 ran them and it was critical that they were present rather than what you are asking -- but I agree with Jay that it is not a great idea for the pressure gradient.
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Re: rod bearing question
I have built BBC race engines using the rod bearing with a hole in the bottom shell that was to be used in aluminum rods with the brass pin and never had any bearing problems when using steel rods with no pin.
Re: rod bearing question
That's the sort of answer I was looking for. If anyone else has some real world examples I'd like to hear about them.