W8MM

Izzone

I'll give u a test run at Sebring

Install myself. And return

For de I can't believe the secrect to the sauce

CRex

I tip my hat to you mate. That's some serious R&D you're doing on behalf of the RL community! With luck, MovIt's technology will be at 1/2 price in 5 years and maybe then I can one rotor on my 991 RS. (not sure which corner tho :ROFLMAO

Would you mind sharing with us your findings on the PCCB from Weissach? Few on this forum have been able to speak to the usability of rotors once delamination starts. Datapoints have been anecdotal at best, and it'll be great to have an educated viewpoint at last... TIA!!

savyboy

Heartening to know 18 months of R&D, posts, and pictures can result in this comment. Wow...

W8MM

The brief way to describe the failure mechanism:

The PCCB rotors are press-formed from a "dough" that contains a "mulch" of semi-random length fibers and then they are high-temperature conditioned to produce a hard solid. Many of these fibers terminate in random orientations at the friction surface of the rotor. If any individual fiber ending at the surface is over-heated enough, it sort of ignites and the fiber end "burns up" and leaves a "worm hole" back into the material, penetrating as far as it is hot enough to continue to burn. It's like a ceramic-tree wood pecker is pecking tiny holes in the friction surface.

If a number of these "worm holes" happen to form closely together, the local surface loses considerable strength from the tunneling of voids in the area. Once this phenomenon advances enough, the rotor face can give up pits or flakes of surface material and things deteriorate very rapidly thereafter.

The guy who ought to know said that while PCCB rotors would generally last the life of a street driven car, if one were to track the same car, PCCB rotors become "wear parts".

The Mov'It ceramic rotors don't have this sort of failure mechanism because they are constructed out of layers of "woven mat" fibres before they are fired and none of the fiber ends can engage the friction surface. Their fiber ends terminate at the edge of the rotor, not the face. No fiber ends on the face, no "worm holes" burn into the face.

CRex

^ Good stuff.

I'll add that the formulation of the rotor appears to differ between vehicle makes. Even though Ferrari and Porsche both source rotors from Brembo SGL, the "chopped fibers" have always been larger and more visible in Ferrari CCMs. Your burnt fiber explanation makes a lot of sense looking at new vs. used Ferrari rotors:

New - Even surface, but difference in shading shows large chunks of fiber beneath the surface:


Used - Pitting from "burnt out" fibers, pits resemble the shape of what used to be the same fiber chunks...


Which inconveniently supports the OP's longtime view: that the Brembo/SGL ceramic implementation is ill-suited for high-temperature applications.

Reading into Brembo SGL literature there are evidently structural differences between Porsche's carbo-ceramics ("CCB") and Ferrari's ceramic-composites ("CCM"). But in the end they're close relatives of one another, being chopped fibers of something suspended in some other ceramic material. The fibers are prone to burning out anyhow. Only way to avoid it is a monolithic, solid-block design.

I guess all this boils down to a cost/performance tradeoff... the majority of the ceramic buyers out there aren't like us and will never see their rotors pushed to the point of fiber burn. Hence it makes sense for Porsche and Ferrari to peddle the more affordably-priced (albeit clearly inferior) product to the masses...

deputydog95

How many track days do you have on your setup now?

TRAKCAR

I'm very interested in these school cars that have them.

We know what we pay for rotors and if these setups have lasted enough days to offset the per day cost, you are back to even, not calculating the convenience of not changing rotors.

deputydog95

Well, I know it's not porsche or skip barber.

savyboy

Relevant threads:

https://rennlist.com/forums/997-gt2-...placement.html

https://rennlist.com/forums/997-gt2-...e-frick-6.html Start at post #86 "In addition here are photos of a set of OE sized CER's after 15 track days or 30-35 hours installed on both a GT2 and GT3 RS. Wear is not-measurable using digital calipers. The surface remains smooth to the fingertip. Original hone and grain marks are visible."

https://rennlist.com/forums/987-981-...-insanity.html

Here is the bottom line- I've used two different sizes of the MovIt rotor on a GT3RS and yet another on a Boxster Spyder. I've measured the rotors with a digital caliper after many hours of hard track use. Let's be conservative and call it 15 days/30 hours on a set of 380mm/362mm rotors. There was no measurable wear. How else can I word that so that it could be any more clear?

A reader now or ten years from now has the option to use "Search" and discover the nature of my contributions to this forum and from there form an opinion as to the reliability of my comments.

The capability of these rotors are no secret to a person who chooses to invest the time to research them. I've no dog in the fight nor any financial connection with MovIt or any of their distributors. Just a passionate enthusiast with a technical background who does their own work on their own car and supports innovative suppliers that offer top of the line solutions

Nick Wong

Savyboy, what's your normal wear rate for steel or PCCB rotors? That may give others a better understanding of how durable the Movit rotors are. For example, I think Trakcar mentioned he changes iron rotors every 12 track days.

savyboy

DeputyDog95 is a perfect example of why they have to do that. He's perfectly happy with his brakes and that's great.

Some of us want a more robust solution, are willing to do our homework and choose to support the suppliers that offer one.

Neither car owner is better or worse than the other, they just have different situations.

savyboy

Nick, I have zero experience with irons on track, so Trakcar is a great reference for those. Folks will claim all sorts of ways to measure PCCB wear but I use surface roughness as my eyeball measurement. As I recall, Porsche also uses this measure in the workshop manual.

If you wanted to be perfectly objective and determine wear rates over time you would use a Portable Surface Roughness Tester/Profilometer in combination with a Coating Thickness Gauge. On both Boxster and GT3 OE PCCB (different size rotors) I wore them down to what I consider 30% remaining over approx 15 track days each. While I allow for a warm up and cool down, I am otherwise very aggressive using brakes and I trailbrake.

So let's say I get 20 track days out of a set of PCCB and they are now eating my pads in one track day because they are so rough. Even if I buy replacement OE PCCB at deep discount from Suncoast, with shipping I am in for $18,000+. If I am planning to do 100+ track days, then I save $40k on rotors alone even if I buy the full MovIt kit with calipers and rotors.

Considered in a vacuum of any other variables and factors:
$18,000*4=$72,000
$32,000*= $32,000 MovIt full kit
Saving $40,000

Obviously the math does not work the same for steels. And some people don't care about rotating mass and unsprung weight, but I do (please can we not rehash that discussion?)

If you are a frequent tracker and a gearhead the value proposition is there, and it is strong, for anyone that takes the time and makes the effort to calculate it.

deputydog95

Agreed.

Izzone

20 days on front iron rotor, pfc
40 on rear oem iron rotor, less for turbo iron rotor

Movie is nice, just not for me