simsgw

It was more important to post the results of those suspension comparisons back to back, but that day also was the occasion of getting my first service on my new Cabriolet.

Some have expressed doubt about the need for break-in with modern manufacturing techniques. My own position is that break-in is desirable and this oil analysis shows why I feel that way. Note the high levels of metals (at the rows where I placed an arrow) and the low "average at this location" in the shaded column. That column includes only a single oil analysis from my 997S. It was taken at about 20,000 miles I believe. Cindy needed my attention at home after that and I had no chance to take further samples with that car. Without boring people with the arithmetic, those values mean the other car (already past break-in) was exhibiting levels below the "universal averages" in the right column. That also means the high levels of this first sample from my new car are caused by break-in. As expected, those levels are higher than they will be later, but still much lower than they would be in less expensive engines. See the remarks by the technician who did the analysis.

It's also interesting to note that an expert I discussed this with is correct about the base stock of the Mobil 1 factory fill being quite capable of going a long interval without breaking down at all. After 4700 miles, the base stock is just fine. See the circled evaluation. I change my oil after break-in simply because it makes my skin itch to leave all those by-products of break-in circulating. (In other words, I'm a stubborn old man. My engineering persona can go to heck.)



Gary

DHill

Gary, thanks for posting. Very interesting. I plan on doing the same and getting my oil changed at Break-In (2000 miles).

Mike in CA

Good stuff, Gary. Thanks. And as for changing the oil after break-in and being a stubborn old man.....count me in.

fester

Thanks gary- this is helpful. it even reinforces 2K miles break in concept.

I had a long conversation with the service manager yesterday when I took delivery of my 991 4S. He recommended not going over 4K for first 1K miles (occassional bursts are ok) - after 1K miles red lining or even taking it to track is ok. He did say though that on highways it typically goes to 1700 rpm and stays there- it's even more important to not keep it there at 1700 rpm but ensure rpm varies continuously.

They are going to conduct a free checkup in a month and I also plan on an oil change at 2K miles.

DrJay

Great info, thanks for sharing! I usually change oil a few times before 4k miles, once at 1k and again at 2.5k and then maybe once more at 4-5k specifically because of the wearing in of the engine and to remove any metal or contaminants from the engine build.

Carrera GT

Thanks for doing the homework.

I did the same thing a decade ago with the venerable 996 GT3 and compared to a (then) 5K mile 993 Turbo engine. We had the same observations.

The general idea is to get a fluids and filters changed somewhere after 1500 to 2000 miles (track or public road driving.) The next used oil analysis at the scheduled 5000 to 7500 or 10,000 distances suggested the engines, though a decade apart, were basically the same and did not have oil degradation after 5000 or 10,000 miles.

We concluded the most useful "service" at 10,000 miles was the correct maintenance of a sticky-oil-film type air filter, mostly related to city driving -- good for the lungs of the car, heaven help the lungs of the driver.

It's difficult (irrational?) to argue a "don't you worry about what the factor says in the manual" position with a new "pride and joy" owner of a 996 GT3, but the blind analysis isn't subject to materialistic romantic notions of what's "good" for the car.
Nevertheless, let the dealer click the boxes in the computer for the VIN of the car and take your money.

Warranty stipulates the revenue share to the oil companies, so perfectly good M1 goes into the recyclers and fresh stuff, goes in behind new filters all round.

I still don't see any evidence of break-in driving practices causing any benefit (or disadvantage.) Regardless of mileage or usage, whether it's a leaf blower or a Le Mans prototype car, every engine should be warm before operating the throttle beyond moderate degrees – even when hot, the engine should not be asked to lug below rpm where throttle response lags, and a driver should refrain from excursions beyond the red-line or the lazy incompetence of using the rev-limiter as a shift light.

STALKER99

Great info.
What would be great if we could compare this to a sample after a 1000 mile break on the same model.

Carrera GT

I'm not sure what a 1000 mile sample tells us, unless you then drain the car and sample again at say 1500, which is what I did with a 997.1 GT3 in 2007, and again at I think 2200 miles (plus or minus) and solely track driving with a "like you stole it" disposition to the break-in driving. I was mechanically "kind" to the engine (warm up, cool down, no lugging, no rev-limiter) but otherwise used "all of it."

The oil continued to show contamination from manufacturing chemicals between 1000 and 2000, so I concluded that, on my next GT3, I wouldn't bother with an oil change till about 2000, which I did, and again at I think 5000 (vague recollection?) to find the oil at 5000 had not degraded at all and the filter itself was not in need of replacement (though that's a little late to decide once it's off the car and peeled open ...) On the current RS 3.8, I did filters and fluids at around 2000 and won't pay much attention to it until the factory service schedule dictates their revenue events.

An extraordinary differential bearing failure at 2000 miles (all track time, including some time trials) showed the gear oil was in perfect condition and the gears and syncro's were showing no signs of wear at all -- the tech described the box as "as if new parts." Aside from the well-documented assembly weaknesses of the GT3, the machinery itself is durable and does not rely upon lubricants and filters to carry away the waste of attrition, as is the usual life of a typical production car drive train.

simsgw

I took mine to the track at 500 miles of course, but I still kept the rpm down. I did that the same way I made sure the engine never droned on at a steady rpm in regular driving. I used the shift controls constantly. I would play them like a keyboard on highways while leaving the car under cruise control (so the tickets didn't break me). On track, I put it in manual mode to prevent downshifts, which occur at an over-high rpm even in touring mode. You have to avoid the kickdown switch at the bottom of the throttle's' travel, but I also kept power down to about three-quarters the whole time. I used sport-plus to get the most crisp shifts, but in manual mode. Then I treated four thousand as the red line. (Alright, it was five for one lap when my very advanced 'student' in a Cayman matched my lap time and I had to restore order to the universe.)

I'm not sure why your service manager would endorse break-in but trouble himself to second-guess Stuttgart on how many miles are needed. I did progressively permit runs to five or six thousand after the first thousand miles, but only as the occasional thing, not a general waiver of the restriction I placed on myself. Break-in doesn't end like throwing a switch of course. After 2,000 miles I saw the red line more often, but it was at something around 3,000 before I experimented with launch control.

One thing I recommend is remembering to use overrun regularly. Downshift manually at speeds that satisfy your current rpm restriction and let the car decelerate on the gears.

Gary

STALKER99

Some of us might not follow the full 2000 mile break.

simsgw

We've already agreed to disagree about engines needing break-in. Porsche does nothing to enforce their recommendation, so it's up to each owner. You pay your money and you make your own decision on how to treat the car.

But I'm not sure how your economics theory fits the modern warranty that has us not doing the first oil change until 20,000 miles or two years. Factory recommendations keep getting longer.

I am old-school personally, and don't like to go more than ten thousand without an oil change. After break-in, I usually change the oil every seven if only to keep track of changes in the oil analysis. To me, it's cheap, and a good practice to monitor events inside the engine. But I called attention to the oil condition in that report because it supports people who prefer longer intervals.

I should add however that the condition report only tells us about the base stock. The additive package is what deals with oil contaminants. It would require a separate analysis that I did not order to determine how quickly the additives are being consumed in their various roles. Obviously, I don't care since I plan to change at that fairly short 7k interval, but fleet operators, who care a lot, do that analysis to decide their policy.

Gary

Detroit Shooter

Gary how do you know that the metal in the oil does not help the rings seat better or let the bearing wear more uniformly initially? I am not saying it does but in my limited experience things are not always what they appear.

A manufacturer must give consise instructions. Keep it below 4k rpm for 2k miles. If they tried to add in language about short bursts and such it would cause more harm then good because of all the questions flowing into customer relations and things like that. I think the keep it simple stupid type thinking may apply to their instructions.

In another post you mentioned lapping in parts because ther was no chance for break in. That metal in the oil does form a lapping compound of sorts.

Not disagreeing but offering food for thought.

simsgw

I can't get excited about it is my best answer. With our cars from the forties, every barber shop had an enthusiast of Babo Break-in. Babo was a cleaning product of the time. These guys would propose mixing a half cup of Babo (or some quantity that varied between proponents) with the oil for the first 100/200/500/1000 miles "to kick start seating the rings". We do use lapping compound on spacecraft components that have to work at full load from first power application, but I'm not sure I'd feel comfortable adding that to the wide range of heat and force levels my 991 engine has seen in the first few thousand miles.

I understand the argument, but if I do have occasion to buy another Porsche, I think I'll still change the oil after break-in. Just a stubborn old man.

Gary

SkandoSchwabe

I'm not fully convinced by the available data. 2-5x differences at ppm level compared with averages? What is the measurement accuracy? Would be interesting to see a comparison between an engine broken in according to Porsche recommendations and one that was driven like stolen from the beginning, under the same external environmental influences. Guess we have to convince a rennlister to volunteer to buy two identical cars and perform the experiment....https://rennlist.com/forums/images/smilies/smile.gif

simsgw

The accuracy is far beyond what we need. We routinely measure such things in parts per billion, which is a thousand times more demanding. Blackstone didn't fake the result to upset your preconceptions. What really matters is no one cares what you do with your own car. I just posted the data for those still trying to decide whether to believe us engineers.

Gary