My tech tells me Porsche recomends replacing the caliper bolts when changing brake pads. I have the 997.2 with teh closed calipers.

That sounds rather extreme for swapping pads in and out on track days.

Any thoughts or opinions from the experts?

 

I have swapped my Caliper Bolts out when changing the rotors, as they are a single use stretch bolt. I also know people that have reused their old bolts, and one guy even took my old one's as they were only used once!?

If it is a PIA, leave the track pads in for the season and swap them at the end for the street pads.

 

I have not come across the term "single use stretch bolt" before. Does this mean that the specified tightening torque for this fastener is sufficient to exceed the yield strength of the material? It is my understanding that the correct torque for a fastener is sufficient to "stretch" the fastener enough such that operating loads do not exceed the clamping force generated by the fastener system, but still stay within the elastic limit of the fastener material. It does not make sense to me that that the specified torque for this application would exceed the yield strength of the fastener material, leading to permanent deformation of the material.

Any thoughts?

 

Check out this thread

http://forums.pelicanparts.com/bmw-r...use-bolts.html

 

NorthVan -

Excellent link - but if I read it correctly, I think that it is saying the same thing that I said - i.e., correct torque (more precisely, tension) is enough to "stretch" the fastener but not enough to permenantly deform it. Is this your reading or am I missing something?

 

You are probably right, however when it comes to brakes I don't argue the fact that they are only $4 per bolt, I change them without question. The thread I linked was merely to show an example of single use stretch bolts, I have removed a bolt and put it side by side a new one and I couldn't see a difference, but I changed them anyway.

 

Fair enough - always better safe than sorry. I am new to the Porsche world, and I am interested in brake details as I am planning on checking my pads and roters and flushing my brake fluid this weekend (after five track days in the last four weeks). Do you have info on pad and rotor service limits, as well as caliper bolt torque specs?

TIA,

Phil

 

Here is a thread that has all the info you need (and then some)

https://www.6speedonline.com/forums/...onversion.html