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Toyota says .0012 - .0019, for main bearing clearances but I am getting .002 - .0025.

From what I have read so far, that clevites like to have .002 - .004...seams like that would be a problem for oil pressure....with 7M oil pumps anyhow.

What kind of clearance have you guys seen using clevite, and what is your oil pressure after rebuild?
 

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Flying Dutchman Pilot!
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I run anything under .003, I see good oil pressure and have never had a clevite or equivalent fail on me. If it were me I would run them.

I've also never had one greater than upper .002s
 

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sounds like your machine shop cut your crank too much
 

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Flying Dutchman Pilot!
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The looseness was in the bearings for me, I mic'd the crank and it was spot on after being ground. Its just how the clevites come.
 

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I put clevites in my 3vze - all clearances were set for the crank to TSRM and the clevites were spot on. Maybe its different for the 7m bearings....

superrunner - I dont think that the bearings necessarially "like" any type of specific clearance, you really should run the recommended clearance for the specific type of engine you are building.

I ran one block with larger clearances and it didnt last very long - low oil pressure at idle was a serious issue.
 

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Flying Dutchman Pilot!
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My oil pressure hits 50psi with 10 30 in it. 2-3 thousandths isnt a huge deal as long as you're closer to 2. I think toyota has their range, but also lists a max and its something like .0028 or whatever. Like I said its never been a problem for me amd I've had 3 7ms with clevites in them.
 

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my crank is at .0025...same with my rods...i yelled at my machine shop, but they tell me im a retard and told me to put my engine together cuz there isnt gonna be a problem...they told me clevites have a higher range then yota bearings.
 

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ALL of my clevite bearings were within TSRM spec....as were those in another engine i built...
 

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joliroger4 how many miles did u put on ur motor? I am curious cuz even after what the engine builders at the machine shop told me im still skeptical that 3 tho clearance is acceptable
 

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Flying Dutchman Pilot!
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I had 3 of them, the one in my car now is still relatively (A couple thousand) low mileage, although I drive it to work everyday (Its the 11.8 motor) and it sees a lot of abuse at 14psi daily. I had another with well over 20k, and that motor went 2 years ago when a hose popped off my fuel pressure regulator and I cracked some of the ringlands. The other was a big mess, but it went about 10k, had other air/fuel problems. I'll say it again, the bearings in all these motors came out perfect. The cranks were ground 10 and 20 under, but thats doesn't matter, I mic'd them and they were exactly 10 or 20, it was always in the bearings. These engines were plastigauged, which isnt an exact science if you know what I mean. Matching up that little piece of paper, you can convince yourself they are .0015 or .003 or anything inbetween. Someones definition of perfect might be a little skewed. Most of them were in spec or close, but I have had them out of spec and close to .003. Your shop is right, it will be ok, but its more of a domestic spec. Look in the tsrm, there is a max spec they give you, which if I am not istaken is close to .003. You should get them within toyota spec, but I wouldn't flip out if they are out a little.

My current bearings are clevex de mexico or something, whatever shit my machinest could get me in a timely fashion, the other motors had ndc and genuine clevites, its all the same exact bearings though, they just buy them from one another. Here they are

http://www2.davidconsentino.com:8000/Dave/Supra/7m105/DSCF0057.JPG

I'd be more worried about hammering in rod bolts and not rebuilding the rod than a bearing thats .0025, lol.

Heres the rest of the engine if you wanna see how it was built:

http://www2.davidconsentino.com:8000/Dave/Supra/7m105/
 

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i went with the toyota bearings. i'm sitting at .0021 on the rods ans .0023 at the mains. i was pissed about this. i almost didn't put the motor together.
 
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So are you all just mic'ing the crank and subtracting from the standard main/rod bore to find the bearing you need? In my quick reading of the tsrm, I noticed the plastigage section... It seems plastigage would be a good way to double check everything, but not a reliable system for determining clearances. Thoughts from those with more experience?
 
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