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Hello all. I took a bit of time a couple nights ago to double check my clearances I was getting on my mains in my rebuild. I used the block and crank codes to get my colors and bought all brand new oem bearings. My plan for the motor is going to be a high compression N/A motor with high lift cams. Just wanting opinions on what I found. I know plastgauge is not the most accurate way, but gives a good idea.





 

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Arouse the DAMPFHAMMER!
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...double check my clearances I was getting on my mains in my rebuild. I used the block and crank codes to get my colors and bought all brand new oem bearings. ...
Hi dcreech0, first I would like to know what are these scratches on bearing #5?

My plan for the motor is going to be a high compression N/A motor with high lift cams...
The stock bearing clearances are very thight, so for a high revving engine they can be set on the upper tolerance of the OEM manual.

OEM manual said:
Mains 1,2,4,5 (0.017~.041mm) or (.0007~.0016″) Max of .050mm or .0020″
Main 3 (.025~.049mm) or (.0010-.0019″) max .055mm or .0022″
Your measures show #5 to #4 0.0015" and #3 to #1 0.001, which is still pretty tight for a high revving engine. What about the next size bigger?

BTW, if you measure with a indirect measurement technique like the press width plastic test, please hold it always rectangular to the plastic (#4, #2 and #1) and the plastic should always placed inline with the centerline of the bearing (#2 and #3).

Markus
 

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it is actually accurate enough that Honda asks to check clearance with Plastigauge in the service manual.
Inside micrometers tend to scratch the very soft bearing shell surface plus you cannot measure across grooved bearing shells for the mains. I have done both methods.
 

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Hi do u have the oem bearing?
Wanting to know what colours u have on main and big ends and what is your code behind the bearing it self

Would help me with trying to find out a colour I am struggling to work out
Thx

Sent from my EML-L29 using Tapatalk
 

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No, KingXP main bearings in three sizes and a ZRP crank, so about as non-OEM as it gets. Three size because of the block. The crank has uniform journals down to a micron or two. Within the accuracy and reproducibility of my gauges, they were all virtually identical.
 

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Arouse the DAMPFHAMMER!
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it is actually accurate enough that Honda asks to check clearance with Plastigauge in the service manual.
Inside micrometers tend to scratch the very soft bearing shell surface plus you cannot measure across grooved bearing shells for the mains. I have done both methods.
We use the precision-inside-micrometer tool for this. There are tools available with a ball end, less tend to scratch the bearing surface. Sometimes the plastic gauge tend to backe on the surface if not properly prepared. To pull it out can be a mess.

I am curious how the KingXP came out after your first disassembly. At Hondapower.de there are several reports that they wear much faster then the OEM stuff. I've never tested it. I don't trust the aftermarket stuff on that part of the engine. I've seen too much bearing damages during my OEM time with changes of materials, thicknesses. This system is so complex even OEM's just do test what they get in endurance tests. Once bitten, twice shy :D.

Anyway or now more then ever, good luck with them!
 

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I have never disassembled the engine since building it. Its sixth trackday is coming next Monday. I found the inside micrometer, a Mitutoyo with 1 micrometer resolution, very arkward to use for the mains. The bearing oil grooves were also not helping.
For the rods, I used a different type of inside micrometer. I always calibrated with a set of size standards I also acquired. I found the plastigauge very easy to use .no stiction or other issues. Journals were all new and in pristine shape, Why should I have issues with trimetal kingXP bearings with proper measured clearances?
most spun bearings you read about are OEM blindly fitted according to the codes without checking actual clearance, the blocks distort over the heat cycles, or fitment of standard size aftermarket shells, again without clearance check.

on the Rover I had good success with Vandervell VP3 trimetal (indium) shells and Mahle Motorsport shells.

the KingXP shells measured to the micrometer to their spec, and I had 3 sizes at hand. This allows for 5 combinations. Fitted good enough for my specs. OEM offers 7 sizes, but without plastigauge or some other metrology, this is next to useless.
 

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I found the inside micrometer, a Mitutoyo with 1 micrometer resolution, very arkward to use for the mains. The bearing oil grooves were also not helping.
2-point or 3-point technology?

...I found the plastigauge very easy to use .no stiction or other issues.
Did you oil treat the surface before?

Why should I have issues with trimetal kingXP bearings with proper measured clearances?
They reported about an higher wear. This has only partly to do with the clearance, it is more about tribological interaction between oil and the bearing and the crank.

most spun bearings you read about are OEM blindly fitted according to the codes without checking actual clearance
Is there an evidence for this?

...but without plastigauge or some other metrology, this is next to useless.
🆙
 

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2-point. First, there was not affordable 2nd hand 3-point gauge for sale at the time. Second, mains are not circular, but have increased clearance at the side to promote oil film formation.
A three point gauge might or might not work.
i used the 2-point at other locations such as the bores and it worked as it should.
Again, I have a collection of inside and outside standard I practiced with until I got my procedure to be spot on.
Without these standards, it is easy to make mistakes. On the micrometer scale, 10C ambient temperature shifts from basement to garage expands parts enough to easily looking a bearing size up or down is needed.
Engine blocks take hours to thermally equilibrate.
Same for the gauges.

evidence:
-read thousands of forum posts
-experienced engine builder got the mismatch of codes and measured clearance confirmed by Porsche. Blocks work and distort over use time.
Codes are only accurate on new blocks. Later they can, but must not match anymore.
-the Block I personally measured did not match with its code clearances.
-the crank exactly measured to its spec, uniformly on all 5 mains and 4 big ends. Same for the rods. This is why I ended with the same shell combo on all 4 big ends
-Honda themself state to replace according to codes, plastigauge and adapt, if out of spec. There is only one reason for that:blocks change during use.

to plastigauge I did whatever it asked for in the manual. Oil or not, don’t remember. It always nicely stuck on the journal.
 

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2-point. First, there was not affordable 2nd hand 3-point gauge for sale at the time. Second, mains are not circular, but have increased clearance at the side to promote oil film formation.
A three point gauge might or might not work.
I see your point. And yes the ID of the bearing in 12-6 o'clock direction is smaller then in 3-6 o'clock direction for that purpose you mentioned.

Engine blocks take hours to thermally equilibrate...Same for the gauges.
🆙

experienced engine builder got the mismatch of codes and measured clearance confirmed by Porsche. Blocks work and distort over use time.
Codes are only accurate on new blocks. Later they can, but must not match anymore.
Sorry, I was to cloudy with my unspecified question and I've read your post not correct. I thought about OEM and wear. But that wasn't your point. I see that now. And yes I agree the bending, pressing, rotating works the bearings over time into the ID of the main bores, same is valid for the crank side, which in addition suffers wear.

...Oil or not, don’t remember. It always nicely stuck on the journal.
Do you remember the plastic gauge brand which King bearing send with the bearings?
 
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