1990nein

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dgjks6

Normal as long as the brake pedal is not vibrating

lurchphil

Time for new rotors. Even though you have center lock wheels, the regular 997 rotors are exactly the same. Any 997.2 rotor is a perfect fit. About $600 for a set of 4 rotors at Pelican parts. The red center lock nubs on the rotors are easily transferrable and reusable. https://www.suncoastparts.com/product/34190100.html You just saved $700! A little loctite helps. I have been using RedStuff brake pads which have been very good and produce little dust. If I can be of help, let me know.
Phil

CAVU

The grooved discs/pads would not be a concern for me at this moment. At 2mm of pad left or brake vibration due to warped rotor then it's time to swap it all out for new. You track so you may choose to swap out sooner.

However, I would be concerned about the perforation cracks at the crossed drill holes for the rear brake rotors (pretty sure those are the rears). 5mm is the max total length and it looks like you have more than a few that are > 5mm. Time to change out the rear rotors and pads if your measurements confirm that. Also, double check the entire circumference of the front an rear rotors for cracks at the edge. If there are any cracks touching the edge, then that rotor is due for a change out. This is all per AllDataDIY for a 2009 C4S. I suspect that it is the same across most if not all 911s with cross drilled rotors.

HenryPcar

You might want to consider after-market slotted rotors instead of drilled rotors. There are cracks on yours and slotted rotors will alleviate that problem.

Petza914

+1

See if there's a Girodisc slotted rotor offering for you're fitment, which I'm sure there is.

I run them on my 928 and they're excellent. 2-piece setup for slower unsprung weight and you can reuse the hat and just replace the disc when they wear.

1990nein

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lmaternick

didn't read any posts....cut to the chase. I don't like groovy rotors. They may work just fine but I wash my car when it's just dusty. Rotors and pads are cheap and easy to replace even as a diy. Rotors don't get groovy till they are old or have been contaminated for a long time.

lmaternick

Now if you really want to get technical a wavy or groovy rotor if designed such could actually have a larger surface area and be therefore a greater braking force. Unfortunately that is not what you are describing. Change the rotors and pads.

Iceter

When I did the first brake job on my '09 C2, I was very surprised and a little concerned about how the stock Porsche rotors grooved. Over time, I realized that it's perfectly normal for these cars. Odd, but normal. And the new, stock Porsche rotors I installed developed grooves very quickly, too.

The rotors seem to be pretty soft and almost sacrificial. When I measured to the bottoms of the grooves, there wasn't enough meat to make it worthwhile to turn the rotors. So while the brakes work fine with these grooves worn in them, the soft rotors pretty much require you to replace them at each brake job if you are fully utilizing all of the pads.