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Discussion Starter #1 (Edited)
I've looked through a BMW torque spec list but didn't see the setting for the 4 bolts in the crank snout.

nevermind, finally found the conformation for the list I have.
 

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I think the damper has more than 4 bolts, here is the spec:






PLEASE NOTE THAT I DO NOT OWN AN M5 AND THIS POST IS NOT INTENDED TO BE ARROGANT. PLEASE READ THE IMPORTANT REVISED DISCLAIMER THAT APPLIES TO THIS POST
 

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I agree it seems a bit odd. They're a single use item.
Torque as you said is 50 Nm then 50 plus 50 degrees.
I found this very high/hard to achieve in practice.....and I only aimed for 50Nm then two 45 degree turns!
When you consider what they're actually doing it becomes a bit more "acceptable".
They are practically the only thing holding the crank sprocket, damper and drive pulley onto the front of the crankshaft.
Therefore driving all 4 variable cams with vanos gears and pumps,
oil pump, alternator, power steering pump, air con. pump.
Kinda starts to make sense when you consider this.
 

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I second-guessed BMW on this. I did the 60 Nm, then by the time I got another 50 deg on them, I was saying to myself, holy **** that's tight! I couldn't believe I was now supposed to crank them another 50 deg. I got another 30 deg on them and said, OK, that's enough, it's not a bloody Centurion tank!

I then pulled out my torque wrench to see what it would take to move the bolts a bit more and when I hit 250 ft-lb, still with no movement, the torx socket split in two. I think a designer got a bit carried away.
 

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Why aren't these bolts left threaded? Sloppy engineering.
 

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Why aren't these bolts left threaded? Sloppy engineering.
I would imagine for the same reason why your wheel nuts are not left-threaded.

The lefty-loosey righty-tighty convention is reversed for rotating equipment when the nut/screw is on the axis of rotation (think fan clutch, VANOS splined gear)
 

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Discussion Starter #9
I would imagine for the same reason why your wheel nuts are not left-threaded.

The lefty-loosey righty-tighty convention is reversed for rotating equipment when the nut/screw is on the axis of rotation (think fan clutch, VANOS splined gear)
If you had left hand threaded lug nuts you would have a seventies Dodge.
On the M62 the crank bolt is called the "Jesus bolt", I had to use a 3/4" breaker bar and a 4 foot cheater pipe.
 

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I believe the Porsche carrera GT right hand side wheel nuts are left threaded.
 

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60 nm 50 deg 50 deg
 
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