speed21

Ok guys, just picked this one up from another forum and thought it may be of interest to the experts amongst us.

I have frequently heard engine break in advice and opinions given which fall contrary to the manufacturers recommendations such as; "drive it like you stole it" and words that effect....but now you have it from the maker along with the rationale.

http://yel.pca.org/porsche-engine-break-in/

Take a look at the last photograph showing the dyno testing of the GT3 engine. You can see that even at 7000rpm the engine is only having minimal load applied (as per the low torque output shown at that rpm).

dentist

Thanks for the useful link! I was really wondering about that one, too...

FORENN

Good piece -- thanks for posting.

toplabels

Thanks a lot for clearing that for me. I just bought my 991s and asked the sales rep about break in period and her answer can be translated to i really dont know thats whybi am making stuff up.

I am glad i came across your thread and will wait thise 2k miles to see what my car can do

Carrera GT

That article is a factory visit, not the official word, and isn't this contracted in part by comments from other factory staff and some in official capacity to represent the company specifically talking about the 997 GT3?

Rainier_991

He-he, more like "if I knew the answer I would not need to sell cars...".
Sounds familiar, very much so in fact.

Rainier

John 996 TT Cab

I did factory tours that included the engine assembly in September, 2010 (2) and again two months ago. On both visits the engines were assembled on an assembly line and not being built by one person like they used to. Lot's of robots also being used on the line. Only saw one robot on the actual car assembly line installing the windshield and rear window though.

Going back in September and will double check again if my eyes were deceiving me.

John in Vancouver

Quadcammer

"The engineer commented that there were many other moving parts other than the engine that needed break-in as well. Wheel bearings, constant velocity joints, tires, brakes and transmission were just some of the other components that were mentioned."

That is the only worthwhile part of the article.

The entire premise of the article is BS. If the "excessive heat" of driving a car hard caused "excessive expansion", then the problem would always exist, new or not. Are your bearings wearing in? certainly not. Not to mention, really the only part of the engine that has any real "wear in" is the piston rings, and they need cylinder pressure to be forced against the walls to confirm with the imperfections in the wall.

I call BS...and stand by my statement that the break in procedure is written by attorneys.

solomonschris

I have never broken in a new car, except to not drive at a steady state (rpm or load) for extended time. I do avoid full load for the first 500 miles or so and I always allow engine to get up to temp before giving it any sort of boot. The idea of breaking in a wheel bearing or CV joint leaves me puzzled.

Edgy01

One of the largest moving parts in a new Porsche is the driver. It usually takes longer for the driver to adapt to the new car than the other way around. I followed their advice when I picked up a car at Zuffenhausen several years ago and that thing still likes using oil!

speed21

So what you are essentially saying, its logical to give consideration to these components, but not the engine or any of its components?

Exactly where?

Not correct. The excessive heat being referred to is generated from the premature overloading of surfaces that have not been allowed to bedded in to 100% of the surface areas in contact.
Of course they are. As stated in my above quote, the running surfaces are subject to a bedding in process which occurs over a set period and procedure, that period and procedure determined by scientific testing of the two components in contact with one another. The need for guesswork and opinion is removed where science is concerned. Component manufacturers spend countless hours and millions of dollars continually researching and developing their products.

Also incorrect. Every moving component within an engine requires a period and a procedure in which to mate correctly with its adjacent running surface. This includes camshaft lobes to lifters, valves to valve guides, valve faces to seats, gudgeon pins to con rod bushes....and so on....etc. To even suggest that only the piston ring to cylinder liner wall contact surfaces require consideration is ridiculous.

[/QUOTE]

Well I've heard it said a good captain always goes down with his ship. lol.

However from a manufacturers position they are obliged to offer advice and warning to the purchaser in a bid to ensure the person gets the best from the product, and preferably without the need to trouble their warranty department. I would certainly agree (based on evidence and experience) that advice is often given but rarely taken, often excused by the user on the basis their engine has survived their ignorance to the instructions/advice given. However the "survival" of their engine does not automatically preclude the running in process was perfected, nor does it guarantee their engine will perform at its best over the longer term trouble free.

A lot of the assumptions on successful running - in frequently read on these forums are merely based upon oil consumption which will always vary between engine to engine anyway. There are numerous things that determine the oil consumption of any given engine such as; operating conditions, oil types, component design etc. With regard to the oil, Porsche use/specify a range of synthetic oils, some which tend to burn more than others, often exacerbated by the operating conditions.

Anyway....fwiw i thought the article gave a good insight to the behind the scenes understanding from the dedicated Porsche engineers that are physically involved in the assembly and testing processes of these engines. And, whilst assembly practices/methods are always subject to change, one thing that doesn't is the need for running surfaces to correctly mate together.

speed21

Wheel bearings, and the greater majority of gearbox and differential bearings have a degree of preload placed on the running surfaces upon assembly. As the surfaces bed in and form a nice even contact across the entire running surface area the preload diminishes. It is during that period that heat is generated far quicker, hence the need for cautious use. The hotter the two surfaces become the tighter the preload becomes as well. Excessive pressure between the running surfaces can cause premature wear and create and uneven contact surface between the two moving parts, even seizure once the lubricant is overheated and is unable to keep up to the demands being placed upon it.

Again. Just because the bearings didn't fail doesn't mean they are in tip top shape.

IndyRob

what I got from the article is I hope I got an engine builder guy who has no bolts and bits left in the basket....

and personally I doubt I have the self control for 2,000 miles at below 4,000 rpm

I plan to try to break it in on the way home. When I get my first friend to go for a ride with me, I predict my official break in period is over.

On my first Boxster I drove it so careful, I didn't generate enough speed to heat up the brakes and they glazed over. I took it in for what I told the service manager was worse than fingernails on a chalkboard. He simply asked this, "did you follow the factory break in schedule?" I said, yes sir, to a T. He said please, never do that again, drive the car the way it was meant and how you want. He said if you baby it, you will have more problems all around. He took the keys, and right in front of the dealership did some zero to 50 fast starts, and without traffic coming, panic stops. He pulled in with the thing practically smoking, and said, there...fixed, no charge. I said so if I do this, you will never void my warranty or refuse me service? He said if I didn't do that, he would have to report me to the general manager to deny selling me one of these fine cars again. In the next 4 years of basic maintainence and oil changes he to this day he inquires to know if I follow is special advice. Later I asked him if there was some computer black box that would realize how it was driven and void the warranty. He again assured me, that as long as I drove safely, to drive the car however I saw fit, and not to worry about breaking it in.

speed21

Brakes isn't an engine....nor does it represent the entire car. The brakes on a Porsche are deliberately over engineered to cater for the huge speeds that can be generated very quickly. Too often users will apply the brakes far too early and ride the brakes lightly down to a steady stop. That is what causes glazing. You can still bed Porsche brakes in properly without flogging the car in the process.

IndyRob

Speed 21, you are right, you are coming from the engineering side and your case is logical, and I don't disagree.

Your post was extremely well written and I was just adding what my service rep said. He did mention that he felt the break in period led to more problems down the road, versus less. It could of just been him being cute, but it was refeshing to hear him tell me have fun with your car, just be safe.

Obviously runnning it at red-line right out of the box for long blasts would not be good, but I think being reasonable and getting on it a little now and then, only after the car is at proper operating temp, will probably do little overall to hurt the car.

Or I will give my car to my grandma to drive to church for 2,000 miles, before taking back to comply with the break in period parameters.

Anyways, it's a Porsche Engine Engineer, and your facts, versus my impatience and my service manager. You are correct!