sbc rod bearing clearance

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95GTSpeedDemon
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sbc rod bearing clearance

Post by 95GTSpeedDemon »

2.1 journal eagle crank
Stock rod
Mild h/c/i, so 6k or so max rpm.

Having an issue with getting bearing clearance where i want it. Shooting for .002 to .0025.
Clevite p had me at .0012-.0015
King bi metal .001 over sized has me at .003 to .0032

With a std volume/pressure pump, would you have an issue with .003? What would be too loose?
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Re: sbc rod bearing clearance

Post by BillK »

Why not try a Clevite "X" and see what you get ? That should get you close to the .002 that you want. I think .003 is too loose.
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Re: sbc rod bearing clearance

Post by 95GTSpeedDemon »

Story of my life. Tried to save a buck, cost me three.

Hxn was about 2x the price.

.0005 thickness x2 sure makes a big difference when you split hairs.

Im guessing standard kings might be closer to .002 then vs the .001 thinner set?
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Re: sbc rod bearing clearance

Post by 95GTSpeedDemon »

just for the sake of discussion, has anyone tried mixing king and clevite?
same mfg people do it all the time. just curious.
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Re: sbc rod bearing clearance

Post by Walter R. Malik »

95GTSpeedDemon wrote: Wed Oct 06, 2021 9:36 am just for the sake of discussion, has anyone tried mixing king and clevite?
same mfg people do it all the time. just curious.
Yes ... use one shell of each.

As a test, I built a 417 Ford engine with mixing 6 different brand rod bearings. No problems or issues at all.
Getting the clearances correct is, 99% of the time, more important than what brand of bearings are used.

Most people simply don't want to spend the money for two or more different sets.
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Re: sbc rod bearing clearance

Post by 95GTSpeedDemon »

I was concerned with an contricity or crush differences between different bearing mfg/thickness/design.
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Re: sbc rod bearing clearance

Post by BillK »

95GTSpeedDemon wrote: Tue Oct 05, 2021 8:47 pm Story of my life. Tried to save a buck, cost me three.

Hxn was about 2x the price.

.0005 thickness x2 sure makes a big difference when you split hairs.

Im guessing standard kings might be closer to .002 then vs the .001 thinner set?
My experience with King is that they vary all over the place thickness wise :( If you call them with the date code from your set they can tell you what the thickness is and if they have a set that will give you the correct clearance. Too much hassle in my opinion which is why I use Clevite 99% of the time.

I would not take a chance on mixing different manufacturers but I have certainly mixed uppers and lowers of the Clevite X and standard to get the clearance I need.
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Re: sbc rod bearing clearance

Post by engineguyBill »

I agree with BillK, am not comfortable utilizing bearing shells from different manufacturers, nor using uncoated shell and coated shell on the same crank pin. You should be able to get to your target clearance using combinations of Clevite shells. Start with checking your crankshaft and verifying that it is absolutely straight and that your main bearing housings are concentric and straight.
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Re: sbc rod bearing clearance

Post by 95GTSpeedDemon »

Rods, but yes, this crank actually is great. Im not an eagle fan, but they did good on this one.

Im going to get more bearings. I dont want to cause issues. Correct Bearings are cheap insurance.
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Re: sbc rod bearing clearance

Post by ClassAct »

My question is why are he clearances so tight? Is the crank on the high side and the rods on the low side? If that’s the case, none the rods to get your clearance. All that dicking around with bearings is just mental masturbation. There is no reason not to open the rods and the mains up a bit to get your clearance as long as you don’t go over the high side of the specs.
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Re: sbc rod bearing clearance

Post by 95GTSpeedDemon »

Crank is 2.0995
I didnt measure the rod without the bearing.
Rods were just machined on the big end.
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Re: sbc rod bearing clearance

Post by rfoll »

BillK wrote: Wed Oct 06, 2021 2:58 pm
95GTSpeedDemon wrote: Tue Oct 05, 2021 8:47 pm Story of my life. Tried to save a buck, cost me three.

Hxn was about 2x the price.

.0005 thickness x2 sure makes a big difference when you split hairs.

Im guessing standard kings might be closer to .002 then vs the .001 thinner set?
My experience with King is that they vary all over the place thickness wise :( If you call them with the date code from your set they can tell you what the thickness is and if they have a set that will give you the correct clearance. Too much hassle in my opinion which is why I use Clevite 99% of the time.

I would not take a chance on mixing different manufacturers but I have certainly mixed uppers and lowers of the Clevite X and standard to get the clearance I need.
Funny, my experience is just the opposite. It's been a few years ago, but my machinist told me he liked the Kings for their consistency. I had a set of standard Clevites that measured .003" on every rod and crank combo I tried. Cranks were all high limit.They went away eventually with a set of -001 bearings. But like I mentioned, that was years ago.
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Re: sbc rod bearing clearance

Post by donclark »

engineguyBill wrote: Wed Oct 06, 2021 10:11 pm I agree with BillK, am not comfortable utilizing bearing shells from different manufacturers, nor using uncoated shell and coated shell on the same crank pin. You should be able to get to your target clearance using combinations of Clevite shells. Start with checking your crankshaft and verifying that it is absolutely straight and that your main bearing housings are concentric and straight.
Curious as to your hesitancy to mix coated and uncoated shells, especially if they are from the same manufacturer, such as Clevite?
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Re: sbc rod bearing clearance

Post by ClassAct »

95GTSpeedDemon wrote: Thu Oct 07, 2021 6:46 pm Crank is 2.0995
I didnt measure the rod without the bearing.
Rods were just machined on the big end.
What does the hole in the rod measure? You are in the middle on the crank. If you still on the low side of the rod, open it up and get your clearance. Way too much thinking going on here. Keep the rod at the high side of the spec or less with your clearance and go.
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Re: sbc rod bearing clearance

Post by 95GTSpeedDemon »

Is this clevite hxn bearing color normal?
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