I've never really understood this concept. When you install your under-drive pulley it says "torque to xx N-M, then turn + 90 degrees". Well, I didn't get out my protractor and my u-d pulley has yet to spin off into outer space!
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James now has: 2008 987S 6 speed
Crashed: 2010 987.2 pdk in speed yellow!
Sold to a cool racer chick: 2004 986 S
YouTube channel: the PORSCHE as seen by NewArt
www.youtube.com/channel/UCohdrH2xHTklM1thxk0KKOQ?