undersize or stock bearings
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undersize or stock bearings
i have 144k+ miles on my gsr, when i changed the oil i put 5w 30 in the engine (bad move) within a 2 days light driving i noticed a slight rod knock. i'm in the process of changing the bearings. Im in high rpm alot, with that said should i buy undersize acl bearings or stock size acl mains and rod bearings?
Thank You
Thank You
#2
Re: undersize or stock bearings
i have 144k+ miles on my gsr, when i changed the oil i put 5w 30 in the engine (bad move) within a 2 days light driving i noticed a slight rod knock. i'm in the process of changing the bearings. Im in high rpm alot, with that said should i buy undersize acl bearings or stock size acl mains and rod bearings?
Thank You
Thank You
you need to measure and if you have a knock your probably gonna need to turn the crank anyway
#3
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Re: undersize or stock bearings
i have 144k+ miles on my gsr, when i changed the oil i put 5w 30 in the engine (bad move) within a 2 days light driving i noticed a slight rod knock. i'm in the process of changing the bearings. Im in high rpm alot, with that said should i buy undersize acl bearings or stock size acl mains and rod bearings?
Thank You
Thank You
#4
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Re: undersize or stock bearings
i have 144k+ miles on my gsr, when i changed the oil i put 5w 30 in the engine (bad move) within a 2 days light driving i noticed a slight rod knock. i'm in the process of changing the bearings. Im in high rpm alot, with that said should i buy undersize acl bearings or stock size acl mains and rod bearings?
Thank You
Thank You
btw I use 5w30 in my 600whp b16 reving 9300rpm all day. dont think your oil caused the problem, if it wasnt to hot.
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Re: undersize or stock bearings
what is the undersized rod bearings used for? the space between crank journal? What are the oversized rod bearings used for? the space between the rod journal?
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Re: undersize or stock bearings
nice response but just say you do not know. I see not to many ppl understands or knows the difference between the 2, obviously they are both made for a REASON. I was under the impression that the undersized rod bearings were used to compensate space on the crank journal from having the crank grinded down. Not to sure on oversized
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#11
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Re: undersize or stock bearings
Undersized would be used with a crank that has had material removed for whatever reason.
Last edited by bambam; 11-03-2010 at 06:35 PM.
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Re: undersize or stock bearings
ok so i was right now what about oversized? Thanks for helping me LEARN SOMETHING, guys need to realize we all were not born with the knowledge of mechanics I am sure we were all "noobs" once.
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Re: undersize or stock bearings
But didn't 1998GsRIntegra explain what "oversized" would be used for? like I said I'm a learner too, but this makes sense to me.
But what everyone is trying to get at I think is: untill you crack her open and measure it than you really can't guess on what the problems is or what you need to do to correct it???
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Re: undersize or stock bearings
I'm a nOOb till I die! So I claim no knowledge and also not responsible for what you do with what I say!
But didn't 1998GsRIntegra explain what "oversized" would be used for? like I said I'm a learner too, but this makes sense to me.
But what everyone is trying to get at I think is: untill you crack her open and measure it than you really can't guess on what the problems is or what you need to do to correct it???
But didn't 1998GsRIntegra explain what "oversized" would be used for? like I said I'm a learner too, but this makes sense to me.
But what everyone is trying to get at I think is: untill you crack her open and measure it than you really can't guess on what the problems is or what you need to do to correct it???
I've never heard of a machinist or engine builder even MENTION an "oversized" bearing. They're referred to as "Undersized" b/c the term is referring to the size of the journal where you're using them. i.e...if you take .020" off the journal, your journal is now .020" UNDERSIZED, so you need "Undersized" bearings. "Undersize" bearings are THICKER than normal bearings. Granted, it's a misnomer..and kinda counter-intuitive.
You guys want to jump on the knowledgeable ppl for "talking sh*t," and you come around and say stuff affirming that not only do you not know sh*t....you don't even know enough to know that you don't know sh*t.
Word of wisdom: It's better to remain silent and be THOUGHT a fool than to open your mouth and remove ALL doubt.
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Re: undersize or stock bearings
Sweet Jesus, Man....you are literally too ignorant to realize where he was going with his statement.
I've never heard of a machinist or engine builder even MENTION an "oversized" bearing. They're referred to as "Undersized" b/c the term is referring to the size of the journal where you're using them. i.e...if you take .020" off the journal, your journal is now .020" UNDERSIZED, so you need "Undersized" bearings. "Undersize" bearings are THICKER than normal bearings. Granted, it's a misnomer..and kinda counter-intuitive.
You guys want to jump on the knowledgeable ppl for "talking sh*t," and you come around and say stuff affirming that not only do you not know sh*t....you don't even know enough to know that you don't know sh*t.
Word of wisdom: It's better to remain silent and be THOUGHT a fool than to open your mouth and remove ALL doubt.
I've never heard of a machinist or engine builder even MENTION an "oversized" bearing. They're referred to as "Undersized" b/c the term is referring to the size of the journal where you're using them. i.e...if you take .020" off the journal, your journal is now .020" UNDERSIZED, so you need "Undersized" bearings. "Undersize" bearings are THICKER than normal bearings. Granted, it's a misnomer..and kinda counter-intuitive.
You guys want to jump on the knowledgeable ppl for "talking sh*t," and you come around and say stuff affirming that not only do you not know sh*t....you don't even know enough to know that you don't know sh*t.
Word of wisdom: It's better to remain silent and be THOUGHT a fool than to open your mouth and remove ALL doubt.
Either way I was reffering to when you are assembling the motor. When you install the bearings and use plastic gauge to check the clearences. For a race na motor you usually shoot for about 2 thousants clearence on the bearings. It allows the motor to run a bit looser than if you were to rebuilt it to factory spec. If it were built to factory spec it would run with less bearing clearence i.e tighter. The reason for running a motor looser is because it makes it easier for oil to lubricate the bearings at high rpm. When I build a race motor I usually end up with a combination of honda yellow and honda pink bearings to end up with 2 thousants clearence. OP if you are rebuilding to factory spec then use the bearings as indicated on the bottom of your block. There is a code that tells you what oem honda bearings to use. You would only use undersized bearings on a factory spec rebuild if you had to have the crank machined.
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Re: undersize or stock bearings
Cool, I never defended my ignorance. Nor did I jump on anyone, was just picking on Bam which I respect highly. true I should keep my unhelping comments to myself, but if it stirred you up enough to answer the OPs question and I learn something from it, well then it wasn't a complete waste was it? Really I was assumeing that the "oversized bearing" he reffered to was meaning it had a larger gap from the journal. But assuming got me in trouble so I'll take your advice and stay out of topics I do not have an answer to, thankz.
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Re: undersize or stock bearings
Cool, I never defended my ignorance. Nor did I jump on anyone, was just picking on Bam which I respect highly. true I should keep my unhelping comments to myself, but if it stirred you up enough to answer the OPs question and I learn something from it, well then it wasn't a complete waste was it? Really I was assumeing that the "oversized bearing" he reffered to was meaning it had a larger gap from the journal. But assuming got me in trouble so I'll take your advice and stay out of topics I do not have an answer to, thankz.
#18
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Re: undersize or stock bearings
I can't tell if I am being reffered to as a moron or not.
Either way I was reffering to when you are assembling the motor. When you install the bearings and use plastic gauge to check the clearences. For a race na motor you usually shoot for about 2 thousants clearence on the bearings. It allows the motor to run a bit looser than if you were to rebuilt it to factory spec. If it were built to factory spec it would run with less bearing clearence i.e tighter. The reason for running a motor looser is because it makes it easier for oil to lubricate the bearings at high rpm. When I build a race motor I usually end up with a combination of honda yellow and honda pink bearings to end up with 2 thousants clearence. OP if you are rebuilding to factory spec then use the bearings as indicated on the bottom of your block. There is a code that tells you what oem honda bearings to use. You would only use undersized bearings on a factory spec rebuild if you had to have the crank machined.
Either way I was reffering to when you are assembling the motor. When you install the bearings and use plastic gauge to check the clearences. For a race na motor you usually shoot for about 2 thousants clearence on the bearings. It allows the motor to run a bit looser than if you were to rebuilt it to factory spec. If it were built to factory spec it would run with less bearing clearence i.e tighter. The reason for running a motor looser is because it makes it easier for oil to lubricate the bearings at high rpm. When I build a race motor I usually end up with a combination of honda yellow and honda pink bearings to end up with 2 thousants clearence. OP if you are rebuilding to factory spec then use the bearings as indicated on the bottom of your block. There is a code that tells you what oem honda bearings to use. You would only use undersized bearings on a factory spec rebuild if you had to have the crank machined.
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Re: undersize or stock bearings
Sweet Jesus, Man....you are literally too ignorant to realize where he was going with his statement.
I've never heard of a machinist or engine builder even MENTION an "oversized" bearing. They're referred to as "Undersized" b/c the term is referring to the size of the journal where you're using them. i.e...if you take .020" off the journal, your journal is now .020" UNDERSIZED, so you need "Undersized" bearings. "Undersize" bearings are THICKER than normal bearings. Granted, it's a misnomer..and kinda counter-intuitive.
I've never heard of a machinist or engine builder even MENTION an "oversized" bearing. They're referred to as "Undersized" b/c the term is referring to the size of the journal where you're using them. i.e...if you take .020" off the journal, your journal is now .020" UNDERSIZED, so you need "Undersized" bearings. "Undersize" bearings are THICKER than normal bearings. Granted, it's a misnomer..and kinda counter-intuitive.
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Re: undersize or stock bearings
An oversized bearing is somewhat new to the automotive industry. A lot of new engines use a cracked cap style connecting rod where the surfaces that the rod and cap meet fit together like a puzzle piece.
This is what they look like, this one specifically coming from a SRT-4. Most of GM's LS engines as well as Ford's OHC Mod Motors have the same style.
If you know how connecting rods are resized, you would know that on a typical "old-school" connecting rod these surfaces are flat so the machinist can cut them to reduce the housing diameter and then be honed back out to spec. Since these are the cracked cap style, you don't want to do that.
Enter the oversized bearings. Instead of cutting the parting surfaces to reduce the bore diameter, machinists are supposed to just hone the rods out about .002" larger and use the oversized bearing for the larger diameter bore.
Last edited by EG1834; 11-05-2010 at 11:36 AM.
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Re: undersize or stock bearings
Again, am I the one being reffered to in this post? I don't mind answering questions at all. I just posted again because it seemed like my vague original post was being mis-interpreted. There is no need to bash each other. I have noticed lately that everyone seems to be really touchy for one reason or another.
As for YOUR Reply, 1998GsRIntegra, I wasn't even referring to your post.
I guess I showed some ignorance of my own. I'd never even heard of anyone refer to an "Oversize" bearing. Granted, this is probably due to the fact that it's not really applicable in a B-Series engine (due to the type of connecting rod used). I've been around old-school GM Small Blocks and Honda B-series. So, never heard of an "Oversize" bearing. I'm guessing it's referring to the bore in the connecting rod being "oversized"?
#23
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Re: undersize or stock bearings
I like to think of HT as a more sophisticated network of people. There are plenty of honda forums out there where the forums are just loaded with how much hp would this be or what parts should I use or what should this dyno threads. I steer away from those type of forums. And I think alot of members on here don't mind helping others and attempt to provide the best help possible. No one here knows everything, but collectively, there are some pretty smart cookies around here and I do think members try to police these boards in an attempt to keep unintelligent or already answered questions to a minimum. It would be more beneficial to just read and learn. And if you do have a question, present it in an intelligent manner so that members can better help clarify things for you.
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Re: undersize or stock bearings