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Advice on oil clearances

Practical Engine Building

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Hi there!

We are building a new vq35 engine for street use, maybe driven somewhat hard sometimes. We where fitting the main bearings and did a measurement with plastigauge to know the clearance(will attach some pics). We found out that the clearance is on the tight end of the oem spec. Whereas the range is from 0.0014 to 0.0018 we are at 0.0014(please see attached pictures). Do any of you see any problem with this tight clearance?

Thanks in advance!

Kind regards,

Vincent

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The best way and I always shoot for is checking bearing clearances with a bore gauge. This and always measuring on an X pattern and up side down as you did.

Plastic gauge is not bad but the bore gauge is the best way.

Looks perfect to me. I like tight clearances and high oil pressure for street engines!

I had my own concerns about this... but, I stumbled upon this article by King engine bearings. I thought it was useful.

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Good article!