Reccomended Bolt Torque

The question of how tight a given bolt comes up a lot on the forums so I thought I’d share what I found in Volvo VIDA software a while back. These values are for aluminum threads and I’m going I’m going to assume the values compensate for some vibration.

Bolt torque and clamping force is a complex topic, so if you decide to use these values, it is at your own risk. I’m not recommending these values as such, just sharing the info I found.

in-lb in red as I’ve heard stories of folks accidentally setting their lbft torque wrenches to those values :open_mouth:


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Are these numbers sort of universal? So if I can identify the bolt type on my rig, torque to that?

Seems pretty standard, crankcase bolts and headbolts for tm kz is 10nm with M6 size

Uh oh. Those are the torque specifications for that bolt screwed into a steel nut.

Tighten them to that specification into an aluminum or magnesium casting and you’ll pull the threads right out.

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Maybe you can provide a reference because these are specified for bolts in an aluminum engine.

Block, head, intake, front chain cover etc, all of the steel bolts screwed into aluminum. I would imagine if these numbers are for steel nuts I’d have over 100 stripped threads at this point.

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In the X30 manual the tightening torques are fairly consistent for various fastener sizes

M5 5-6Nm
M6 8-10Nm
M8 18-22Nm


This matches what I’ve been using. Thank you for posting.

I wish kart and component manufacturers posted this so that there wasn’t any ambiguity.