Delphos, Ohio! I have a bunch of family there. You have to be the only 911.

You mustn't own Big Red brakes...

Or, you're so rich, money is no object. Take a gander at the prices...

Many manufacturers are more concerned with customer complaints of brake squeal than rotor or pad life. Thus, they install softer pads to mitigate any potential noise. Who knows, perhaps softer cast iron rotors as well (?). I"m sure you've seen the spent pad material end up covering wheels and wheel covers.

And comparing rotor life on another vehicle isn't a good comparison with Porsche rotors. Most cars are underbraked with thin, small diameter rotors and small, single piston calipers. In addition, many/most car dealers typically replace rotors along with pad replacement. Preventative measures or to "pad" the repair bill. Installing new rotors is more profitable than time spent turning good rotors. You decide.

As described, brake pedal pulsations can be due to a transfer of brake pad material onto the rotor surface. If that's the case, try a surface conditioning disc to remove.
https://www.aaabrasives.com/catalogsearch/result/?q=surface%20conditioning#q=surface%20conditioning &idx=production_default_products&p=0&nR%5Bvisibili ty_search%5D%5B%3D%5D%5B0%5D=1&is_v=1

As for cheap rotors; yes, they're out there:
NEW Porsche 930 3.3l 78-79 Pair Set of 2 Front Vented Disc Brake Rotors Genuine | eBay

Sherwood

If saving less than a hundred bucks on a system as critical as brakes is important, perhaps owning a german car isn't for you. I really don't mean to be flip about it, but these cars aren't necessarily cheap to run..

Oh yeah? Try a set of PCCB rotors for a modern Porsche. #CaptainOneUp

The guy never said anything about big reds, and yes, I have two cars with them.

The phrase "false economy" comes to mind when describing an antiquated process to rehab a safety item that should probably be replaced.

Oh, and the fact that the OP can't find anyone to do it pretty much confirms that the industry has rejected this process out of hand. If someone could make money at it, they would be doing it.

Let's be honest, 95%+ of us don't own a modern 911. I wasn't one upping, simply stating replacing standard brake rotors vs Big Reds is about a 6-8X difference...

Doubt phasing out rotor turning was due to safety, rather another cash grab the higher ups figured out, no?

Sure, you had Bubba who'd take your rotors below minimum in the past, but I don't think a passenger car would stress rotors enough to be a real concern. I've seen dozens of rotors ground down to the cooling fins that didn't explode. Maybe this why the industry stopped? Dunno.

On a racing car, sure, R & R. But on a street driven 911, can't see truing up the face of a rotor a bad thing. People sometimes skip refacing and throw another set of pads on a worn rotor without a hitch.

We've become such a throw away society...:)

If manufacturers thought resurfacing rotors was an antiquated process, they wouldn't have spec'd a wear limit for it. But they do, and service depts./some repair shops still routinely replace rotors that are still serviceable. What does that tell you about that industry?

Should one replace rather than resurface flywheels too? How about automatically replacing tires after 5 years, regardless of condition, because the manufacturer suggests it? Paying more than the item or service is worth or deserves is wasteful. Again, it's your money and up to you.

Sherwood

Get outta here! That's too funny. Yeah, I'm the only 911 cruising around town.

I see you threw flywheels and tires into the mix - kind of apples vs. alfa romeos there. Check pelican's rotor selection; the vast majority of rotors are under $150 each. So ask yourself if the time it takes to remove both wheels, both wheel hubs, the rotors, then measuring the rotors is worth all of the effort just to put the old ones on ESPECIALLY since most people on this thread have lost sight of the fact that the OP was complaining about the performance of the old rotors in the first place.

Sounds tight to me, tight as a crab's azz that doesn't leak underwater.

So because I own a classic German car I'm just supposed to piss away money? Is that what you're saying?
I looked at it from a standpoint that one rotor was only worn by .25mm from new. The other was only worn .50mm from new. So rather than piss away the money on rotors, I spent $25 to have the rotors turned and spent $60 on a low dust performance brake pad. All told, I'm still $19 to the better and should have brakes that function like new.

Warped rotors are one thing. BTW, the labor involved to R&R a rotor (to turn or replace) is the same. The difference is between the cost of two rotors (e.g. $300 + shipping vs turning both for $30.). Would you be against DIY or have your tech to R&R for +$200 labor? Again, your choice (better to have choices). I pick and choose parts and processes depending on the parts and process. Hey, it must be great to have a bunch of cars as well as a big checkbook. Best wishes.

Sherwood

Have you measured the runout on the rotors? How do you know they're warped?

The shop where I had them turned checked them for run out.

I'd like to point out that I could find plenty of places that resurface rotors. My problem was that the machines they were using were too NEW or they didn't have the flared adapter to mount the rotor to the machine. Once I took it to my local parts place that has been resurfacing rotors for as long as I can remember, there was no problem. They had multiple "cones" for the different diameter of the center hole in the rotor. They are a carquest (now owned by Advance Auto) store and sell new rotors. They only suggest new rotors when the original are too worn to turn.

There's a senior living center down the street from Taco Bell that my grandmother is at. She's 105 and the oldest person in Delphos at this point. Small world!

To muddy the rotor-turning waters, the process to resurface brake rotors is similar to resurfacing flywheels and brake drums. Typically, a lathe tool is used to true the friction surfaces. However, the process doesn't account for hard spots that develop in the surface due to heat. In that case, the lathe tool will merely skip over the hardened work surface and result in an uneven cut. In addition, the lathe tool could also create a fine spiral pattern, much like cutting grooves in vinyl records (vintage playback medium for you young grasshoppers).

The result is that the friction material (brake shoes, brake pads) wants to act like a phonograph stylus and traverse the grooves until the mechanism restrains further movement. A clicking noise is symptomatic of such a phenomenon as a result of this. For that reason, resurfacing "connoisseurs" recommend using a motor-driven rotary stone, not a lathe tool, to grind a new frictional surface or if a lathe-tool is used, to break up the spiral pattern by working the finished area with a flap disc.

Tell that to your new car dealer service manager. :)

Sherwood

The thing is there are a lot of rich guys on pelican. But most of us are not. Many of us have had old Porsche cars for years and we are not millionaires. There is no safety problem if rotors are within spec. The rotors you are driving on now are within spec. The bottom line is all the Porsche dealers and Porsche independents will not turn rotors because they make a lot more selling new ones. It is kind of like cheating the customer.

I know exactly where you're talking about. A friend of mine does the event planning there. If you have other family around, tell them to come vote for my car at Canal Days! I never win! A good friend that runs the car show even created a foreign sports car category just for me and I STILL can't win. "No respect... No respect I tell ya"

Easy there tiger, don't take my word for it - read Steve@Rennsports comments on turning rotors:
https://rennlist.com/forums/911-forum/977018-turn-rotors-on-911-a.html
http://forums.pelicanparts.com/porsche-911-technical-forum/397161-brake-disc-question.html
http://forums.pelicanparts.com/porsche-911-technical-forum/491316-930-brake-rotors-thickness.html

I'm certainly not advocating wasting money - my point is that there are things you don't skimp on -brakes and steering being at the top of my list, and that there are other marques that are more economical to maintain.

"I NEVER machine/turn rotors on a car unless they are 322mm or larger and will never be used on a race track."
Not sure what he's talking about. Stock thickness is 24 mm. Minimum is 22mm. I'm still above minimum even with the turning that was done. There's a reason they list a minimum thickness. Having brake rotors turned isn't really "skimping" IMO. I have had the rotors turned of almost every vehicle I have owned including an F350 that was used almost strictly for pulling a 3900lb trailer with machines weighing over 8000lbs. I have never suffered a failure due to turned rotors. I have OTOH suffered problems related to stuck caliper pistons and a brake line rupture. So if I were to call something "skimping" I'd have to say it's rebuilding calipers or driving around on old brake lines.

He means 322 mm in diameter, not thickness. And calipers are meant to be rebuilt, hence the availability of replacement pistons and seals. Rotors are a known disposable part.

Is that why there's a minimum thickness rating for rotors? Because they're supposed to be thrown away? Think about what you're saying before you say it.

Don't get me wrong here. I'm simply going to end the myth here that rotors are supposed to be tossed. It's a silly notion that is based on no real fact. If all four brakes are working properly, there's no reason you shouldn't turn rotors unless their is noticeable bluing of the rotor meaning they have gotten WAY too hot. Then, yes, you get rid of them because they have lost some of the tempering. Otherwise, turning a rotor does not make them any less safe or places like Oreilly's wouldn't do it nor would the shop that did mine.

If you had purchased new rotors, I bet you would have won next time. :D

I never thought of it that way. Maybe I'm dealing with a far more sophisticated group of judges than I was thinking.
On second thought though, I know most of the judges so... no, not really. The worst part is, I was a judge one year and STILL lost. :eek:

Cab,

When I first read the thread, I was solidly in the "just buy new ones camp." Now, you won me over, I think since rotors have become so cheap, most of us just replace, or we've run them so long that they couldn't be turned safe.

On the other hand is my DD Toyota which are probably cheaper to buy new than get turned and since I park it outside, they usually have a "nice" rust crust on the outer edge.

One less thing in the landfill, well they do get recycled, but that takes energy too.

Best,
Rutager

There is a minimum thickness because when the rotor reaches that minimum, it is designed to be discarded. It's not a myth at all. If they are too thin, you THROW THEM. Not sure if you are arguing that fact.

Yours aren't too thin, however. They just aren't working the way you want them to.

Finally, back when Porsche made the rotors for your car, they were the only ones making them. If you wanted a replacement, they were probably $500 each from the dealer. Now, there are aftermarket rotors that cost next to nothing.

What year is your car?

Pelican has rotors for a 1983 for example, that are TWENTY TWO DOLLARS. That's right, 22 bucks for a rotor.

Pelican Parts - European Automotive Parts and Accessories - Porsche • BMW • Mercedes • Volkswagen • Audi • Saab • Volvo • MINI

Why would you ever fcuk around with turning them when they can be had for 22 bucks?

Just the bandwidth you wasted on this thread is worth 22 bucks alone.

This is not true at Porsche. Gotta be at min thickness to replace or it can come back on the service dept in the way of bad review or unprofessionalism. Now if the customer wants replacement that's their prerogative. In my experience with OE Porsche brake components there is rarely ever a pulsation issue even after rotors are a way past min thickness.

One thing is certain here. The amount of time you have spent arguing whether rotors should be turned or not on a thread that wasn't asking IF they should be turned but rather whether others had difficulty finding somewhere to turn them has been wasted.
Please... don't hesitate to move along now and stop wasting your time.

Amen...

As long as your rotors are in spec and don't show any signs of drastic overheating or in the case of some cheaper made in China rotors you have rusting from the inside out, I wouldn't hesitate to get a set turned. The most important part is figuring out why the buildup or overheating occurred. I know in my case it happened a few years ago when I first got the car on the road and didn't take the time to really inspect the overall braking system other than to replace the fluid. I later found a few of my calipers had stuck pistons.

One more side thread for brake geeks
I asked if people thought the direction of rotor air scoops (in the middle of the rotor) mattered about a week ago on Cayenne forum (Early Cayenne Turbo's are HEAVY cars, big brakes) and I got a ton of opinions and learned more than I though I would.
https://rennlist.com/forums/porsche-cayenne-forum/1005857-rotors-does-l-r-side-really-matter.html

There is no "opinion" on this subject. Different part numbers left and right. The engineers at Porsche got this right.