Tackling the demon bolt...

Leuz

OP, so I just fought with these bolts last week. It took me 3 days to get those demon bolts off trying everything. I tried tons of options ($$$). This is what worked for me.
- 6 sided 14mm socket, 3/8" as otherwise it won't fit
- 1/2" to 3/8" adaptor
- 1/2 ft 1/2" extension + another 1/2" extension to be able to reach out of the engine bay. The key here is to have as few extensions as possible 2x1/2ft would be ideal I guess
- 27" 1/2" breaker bar (the one you can find at harbor freight)
- gallons of pb blaster, wd40 whatever you have
- 3 days
The driver side was what took me longer as it seemed it did not want to come out. Finally it loudly snapped and came off. The passenger side didn't snap, it literally "broke in half" from the torque I applied to it luckily it broke towards the end of the nut stud so I was able to get the cat off.

Side note: the Service manual says those nuts have a torque of 43lb/ft, those demon bolts are NOT like that on this planet.

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2013 PW 370Z Touring+Sport, NAV
Tint 35% side, 18% back | RJM clutch pedal | ZSpeed SS lines | Stillen Gen3 CAI | Fast Intentions HFC and TDX 12'' CF CBE | UpRev