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I was looking through my manual for the correct bearing clearance on factory 6.1 crank journal and it reads

Connecting Rod Journal Diameter 53.992 - 54.008 mm 2.125 - 2.126 in.
Bearing Clearance 0.020 - 0.074 mm 0.0007 - 0.0029 in.

.0007 is out to lunch should I just say .001 per inch of journal for minimum and use .0029 as a upper limit ?
Thanks
 

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2020 Dodge Challenger Hellraisin Scat Pack
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I was looking through my manual for the correct bearing clearance on factory 6.1 crank journal and it reads

Connecting Rod Journal Diameter 53.992 - 54.008 mm 2.125 - 2.126 in.
Bearing Clearance 0.020 - 0.074 mm 0.0007 - 0.0029 in.

.0007 is out to lunch should I just say .001 per inch of journal for minimum and use .0029 as a upper limit ?
Thanks
If you are rebuilding an engine 0.0007" should not faze you. Heck man that's almost a thousandth of an inch.

For a street engine, if you have some control over the bearing clearances you should strive to keep them towards the lower end of the acceptable clearance range. This makes for a quieter running street engine, and reduces the oil budget the engine requires. (Big clearances mean more oil flowing out the bearings which means the pump needs to supply more oil.)

For an engine used in competition the clearances should (probably) be opened up some. Absent some "official" word on this (either from the factory and its competition engines department or from noted engine builders who share this info) I would strive to keep the clearances say from 1/2 to 3/4 of the allowable clearance. 'course, dyno/track testing may find the engine makes better power, or runs longer, with tighter bearing clearances. But generally more bearing clearance -- within reason -- is better for a competition engine.

Be sure you check the clearances of every bearing and across the full width of the each bearing. While I had the dial bore gauge tools, inside micrometers, and outside micrometers to determine bearing clearances, I used Plastigage to do this.
 
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