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Blue62

1,861 posts

38 months

[news] 
Thursday 4th October 2012 quote quote all
Love this issue, there are plenty of knowledgeable folk who will tell you it's better to rev an engine, but this clearly conflicts with what is in the handbook. FWIW I am on my 6th new 911 and have always kept it to 3000rpm for first 500m, then up to 4000rpm for next 500m and then gradually opened it up. By the way that's metres not miles.

Mermaid

17,782 posts

57 months

[news] 
Thursday 4th October 2012 quote quote all
nsm3 said:
..

Do what the handbook says, most "salesmen" don't know jack about cars anyway, they could just as easily be selling ball point pens.
+ 1, apply common sense.

shoestring7

4,914 posts

132 months

[news] 
Thursday 4th October 2012 quote quote all
REALIST123 said:
Here we go again. Below is what Porshe seem to think, apparently it's not just about the pistons and rings.....

Some of the engines are also randomly selected to be tested on a dyno stand before they are installed into the car. The assembly plant has 5 dyno rooms located directly off the production line. The day I was on the tour, there were around 40 engines lined up on dollies. Some of these engines were in the process of being tested for quality control purposes. Once the engine is bolted onto the dyno, warm water is circulated throughout the engine to bring it up to temperature. The operator then starts the engine and checks for the correct pressures and temperature before the actual test begins. Engine speed is then increased in RPM steps to about 80% of its red line (the engine’s maximum RPM). The entire engine run takes around 30 minutes. Since each engine type (Turbo, GT3, Boxster or Carrera…) has a different red line, all of the data is recorded and analyzed after the test is completed.After the engine is turned off, the engine is again checked for seal leaks and its actual HP is compared to its advertised HP. To pass final inspection, the engine has to develop, at a minimum, 100% of what its advertised HP rating is. Also, the engine cannot produce more than 5% over that same advertised rating. If the engine falls out of those parameters, the engine is rejected and then torn down to determine why it did not deliver the anticipated HP.
When the test was completed, a Porsche engineer came over to review the results. I couldn’t resist asking the question that I had been searching to find an answer to for all these years. I asked “why does Porsche feel it is safe for a new engine to run at nearly full throttle in the factory, while the customer must keep the engine speed to no more than 4,000 RPM for a 2,000 mile break-in period?” I thought that was a logical question and if I do say so myself-well stated! The engineer replied, “Herr Koop, you do not understand (that I already knew). When we do our engine test, the metals inside the engine never reach the temperatures they would when driven on the street since the test session is fairly short. In other words, the bearings, pistons and cylinders never get a chance to thermally expand to their maximum. Therefore, there is little wear on the moving components. But when you drive a car on the street, the engine parts expand considerably more because of the heat being generated from the engine running for an extended period of time. No matter how tight the tolerances are, there is always a slight amount of expansion in the material. The moving parts can wear quickly if exposed to excessive heat and not always in a uniform way. We also constantly vary the speed and allow the engine to run at both high and low RPM’s”.

“Porsche wants the engine to break-in slowly, which means it needs to maintain a lower operating temperature (below 4,000 RPM) and to allow all parts to adjust (wear-in) within their own thermal expansion parameters. This is also the reason why Porsche wants the owner to vary the RPM throughout the break-in period; therefore the engine doesn’t get use to one operating temperature range”.

“Porsche has been using Mobil 1 Oil since the early 90’s. With its superior lubricating properties, it takes many miles of driving (without getting the engine too hot) before the components actually seat (or break-in). Porsche’s own tests reveal that after 2,000 miles have been driven, all of the moving parts have had a chance to wear into their adjacent surfaces and then an increase in engine RPM is permissible.” I replied, “JA DAS SOUNDS GUT, when you explain it that way, it makes a lot of sense.” I thought to myself “You Dummkopf, why didn’t you think of that”.

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.

So breaking it down into layman’s terminology, it all comes down to; higher RPM equates to more heat, which leads to greater expansion. For a new engine, that can mean uneven wear on certain parts if excessive heat is allowed to build up. In Porsche’s opinion, the thermal expansion of different parts and various materials need time to adjust to one another. Porsche’s time frame for that to occur is calculated to be 2,000 miles, with the heat restriction being 4,000 RPM. So simple; who woulda thunk.
Sensible stuff, although I suspect there's a difference between a quick run up to the redline in 3rd on a motorway on-ramp (when the engine's properly warm) and a flat-out 30 minute Autobahn blast.

FWIW I took it easy for a couple of hundred miles then tried to build pressure in the cylinder head (to seat valves and rings) by using ~80% throttle in the midrange. After 1000miles I didn't hesitate to drive it like I stole it (again when properly warm). My (2.7 Cayman) engine was smooth and economical.

SS7

Xps911

254 posts

33 months

[news] 
Thursday 4th October 2012 quote quote all
Phooey said:
On collection, it's tradition to leave 2 black lines exiting the showroom.
lol

TB993tt

1,310 posts

127 months

[news] 
Thursday 4th October 2012 quote quote all
REALIST123 said:
Here we go again. Below is what Porshe seem to think, apparently it's not just about the pistons and rings.....

Some of the engines are also randomly selected to be tested on a dyno stand before they are installed into the car. The assembly plant has 5 dyno rooms located directly off the production line. The day I was on the tour, there were around 40 engines lined up on dollies. Some of these engines were in the process of being tested for quality control purposes. Once the engine is bolted onto the dyno, warm water is circulated throughout the engine to bring it up to temperature. The operator then starts the engine and checks for the correct pressures and temperature before the actual test begins. Engine speed is then increased in RPM steps to about 80% of its red line (the engine’s maximum RPM). The entire engine run takes around 30 minutes. Since each engine type (Turbo, GT3, Boxster or Carrera…) has a different red line, all of the data is recorded and analyzed after the test is completed.After the engine is turned off, the engine is again checked for seal leaks and its actual HP is compared to its advertised HP. To pass final inspection, the engine has to develop, at a minimum, 100% of what its advertised HP rating is. Also, the engine cannot produce more than 5% over that same advertised rating. If the engine falls out of those parameters, the engine is rejected and then torn down to determine why it did not deliver the anticipated HP.
When the test was completed, a Porsche engineer came over to review the results. I couldn’t resist asking the question that I had been searching to find an answer to for all these years. I asked “why does Porsche feel it is safe for a new engine to run at nearly full throttle in the factory, while the customer must keep the engine speed to no more than 4,000 RPM for a 2,000 mile break-in period?” I thought that was a logical question and if I do say so myself-well stated! The engineer replied, “Herr Koop, you do not understand (that I already knew). When we do our engine test, the metals inside the engine never reach the temperatures they would when driven on the street since the test session is fairly short. In other words, the bearings, pistons and cylinders never get a chance to thermally expand to their maximum. Therefore, there is little wear on the moving components. But when you drive a car on the street, the engine parts expand considerably more because of the heat being generated from the engine running for an extended period of time. No matter how tight the tolerances are, there is always a slight amount of expansion in the material. The moving parts can wear quickly if exposed to excessive heat and not always in a uniform way. We also constantly vary the speed and allow the engine to run at both high and low RPM’s”.

“Porsche wants the engine to break-in slowly, which means it needs to maintain a lower operating temperature (below 4,000 RPM) and to allow all parts to adjust (wear-in) within their own thermal expansion parameters. This is also the reason why Porsche wants the owner to vary the RPM throughout the break-in period; therefore the engine doesn’t get use to one operating temperature range”.

“Porsche has been using Mobil 1 Oil since the early 90’s. With its superior lubricating properties, it takes many miles of driving (without getting the engine too hot) before the components actually seat (or break-in). Porsche’s own tests reveal that after 2,000 miles have been driven, all of the moving parts have had a chance to wear into their adjacent surfaces and then an increase in engine RPM is permissible.” I replied, “JA DAS SOUNDS GUT, when you explain it that way, it makes a lot of sense.” I thought to myself “You Dummkopf, why didn’t you think of that”.

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.

So breaking it down into layman’s terminology, it all comes down to; higher RPM equates to more heat, which leads to greater expansion. For a new engine, that can mean uneven wear on certain parts if excessive heat is allowed to build up. In Porsche’s opinion, the thermal expansion of different parts and various materials need time to adjust to one another. Porsche’s time frame for that to occur is calculated to be 2,000 miles, with the heat restriction being 4,000 RPM. So simple; who woulda thunk.
That's a good read thanks for sharing.

If they only take said engine to 80% of red line, that is only about 5500rpm in a 911 engine (of most iterations) so how can they measure maximum power when said power doesn't occur until higher up the rev band so they must actually run it up to the limiter briefly ?

When German engine builders Ruf and RS Tuning build a brand new engines they tune them on their engine dynos, I always presumed they must run it in first but for how long ?
Point is when they tune the engines they are held under load at maximum rpm and their certified power/torque diagrams display full load curves which are recorded right up to maximum rpm, usually 7000 on Mezger turbo motors.

They also state that the power may increase after a few thousand miles due to bedding/running in.


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Mutema

429 posts

36 months

[news] 
Thursday 4th October 2012 quote quote all
I was looking for a soft copy of my manual to save space and hassle lugging the telephone book sized manual that supplied with the car. I ended up with a US PDF which I compared to my UK hard copy and the run in instructions were completely different (ignoring all the spelling mistakes in the US version)...

I can't remember who said it to me but the suggestion was that the break in was also for drivers with delusions of invicibility now that they were in a Porsche. Having models referred to as 'widow makers' doesn't make good PR and stops their customers buying the next model.

itsybitsy

1,567 posts

71 months

[news] 
Thursday 4th October 2012 quote quote all
TB993tt said:
They also state that the power may increase after a few thousand miles due to bedding/running in.
i think is true of standard engines after running in 3 engines and now on my 4th what i have noticed is engines seem more perky and better mpg once you get to past 5000miles.i seem to recall it use to be said a golf gti mk1/2 wasnt fully run in until 60K?
i remember the days of running in 2 strokes it was said dont let the engine get to hot (or dont go on long trips)to avoid heat seizures in first 1000 miles

bench testing an engine has no rolling resistance and so revs freely without straining the engine unlike when coupled to a gearbox ,driving the wheels and dragging a ton of bodywork

i stand by break in gradually and vary the rpms then after first 500+miles increase the rpms and when mileage is over 1000+miles up to 80% in all gears every now and then when engine is upto temp..more harm is done by staying at a constant rpm for the whole period.

TB993tt

1,310 posts

127 months

[news] 
Thursday 4th October 2012 quote quote all
itsybitsy said:
bench testing an engine has no rolling resistance and so revs freely without straining the engine unlike when coupled to a gearbox ,driving the wheels and dragging a ton of bodywork

Bench testing has resistance to simulate full load in 6th gear ie same resistance as on the road, in fact an engine dyno can brake an engine even more severely to any road.
Exhibit A, a Porsche turbo gearbox shaft attached to an engine dyno which failed due to high torque, this won't happen on the road since wheels will spin before these splines bend but extreme engine dyno loading


Exhibit B, loading and heat
http://www.youtube.com/watch?v=1Q6LwaF9LyM&fea...

Geneve

2,987 posts

105 months

[news] 
Thursday 4th October 2012 quote quote all
I'm no engineer but, have quite a bit of experience of engines from Rotax to Rolls Royce Jet Turbines.

In some applications, by necessity, great care is taken during the start up, operation, and shut down procedures to preserve consistant performance and reliability throughout the engine's pre-determined life (measured in hours).

In racing, the engine is needed to produce maximum performance for a shorter duration between re-builds, so the break-in is very brief and quite aggressive. As mentioned above, you get better compression by giving it plenty of beanz early in its life.

The lengthier, sympathetic running-in period, probably means that the engine may not reach optimum performance for 20,000 mls, and may never reach it if it doesn't go through sufficient high rpm heat cycles regularly.

The Wookie

10,013 posts

114 months

[news] 
Thursday 4th October 2012 quote quote all
FWIW I had two 997 Gen 2's consecutively for 6 months apiece after winning a Porsche championship. Despite the fact they weren't mine I ran them in in accordance with the manual, once past that I used the revs and performance but didn't abuse them. Generally I covered about 12k in each of them under very similar driving conditions.

The first one was absolutely perfect when I handed it back, the second had a gearbox vibration in 4th, emitted a huge cloud of blue smoke on startup and had gone through a couple of litres of oil by the time I handed it back.

Make of it what you will.

GuitarPlayer63

108 posts

35 months

[news] 
Thursday 4th October 2012 quote quote all
is this the same running in period that all the OPC's demonstrators are lovingly afforded?

ChrisW.

1,792 posts

141 months

[news] 
Thursday 4th October 2012 quote quote all
I ran mine in gradually as others have suggested, --- it has now done just over 10,000 miles.

The engine is now 15% more economical than it was when it was brand new, and oil changes excluded, I have added only 2 x 350ml oil --- just enough for the gauge to return to max from one notch below max.

The only explanation I can see for this data, is successful running in of the engine.

cmoose

25,395 posts

115 months

[news] 
Thursday 4th October 2012 quote quote all
GuitarPlayer63 said:
is this the same running in period that all the OPC's demonstrators are lovingly afforded?
Quite.

red_slr

1,483 posts

75 months

[news] 
Thursday 4th October 2012 quote quote all
I try and stick to the 500 miles at half revs then build upto full revs by 1000 miles and oil change.
Go easy on the brakes for the first 200 miles. Avoid letting the engine idle in the first 1000 miles.

ChrisW.

1,792 posts

141 months

[news] 
Friday 5th October 2012 quote quote all
It is at least a part of the fun of buying a new car --- and a great chance to get to know it in order to avoid trashing it ---

Why would anybody not run a car in ?

And what would that say about the purchaser ?




Manks

7,643 posts

108 months

[news] 
Friday 5th October 2012 quote quote all
GuitarPlayer63 said:
is this the same running in period that all the OPC's demonstrators are lovingly afforded?
Hands up, I have had Porsche demo cars and driven them like they were run in even with 10s of miles on them. Why? Because I wasn't told any different and I thought until recently that running in was not required.

But having had a couple of these cars when new, and again when they have done a few thousasand miles they seem no worse for the experience.

I am also doubtful as to whether the Porsche Experience cars are run in to the tune of 1850 miles.

REALIST123

3,739 posts

39 months

[news] 
Friday 5th October 2012 quote quote all
Manks said:
GuitarPlayer63 said:
is this the same running in period that all the OPC's demonstrators are lovingly afforded?
Hands up, I have had Porsche demo cars and driven them like they were run in even with 10s of miles on them. Why? Because I wasn't told any different and I thought until recently that running in was not required.

But having had a couple of these cars when new, and again when they have done a few thousasand miles they seem no worse for the experience.

I am also doubtful as to whether the Porsche Experience cars are run in to the tune of 1850 miles.
I am sure you're right about he PE cars and other demos, and quite accept what you say about showing no ill effect after a few thousand miles.

I believe you see the results of a hard start in life much later, with high oil consumption, premature bore and valve train wear, with a corresponding reduction in performance.


wilkos

128 posts

124 months

[news] 
Friday 5th October 2012 quote quote all
Am I the only one who finds this funny? If you have a new Porsche, then the chances of how you break it in having any effect on your life is minimal. You'll likely trade it in before the warrantee runs out, and the dealer won't ask "did you run it in" when he kicks you in the nuts with a trade value!

Enjoy the cars, drive how you want, and accept that you can be careful and crap happens, or you can enjoy it and crap may or may not still happen.

I am an engineer, and I'd say, let the fluids warm up, and then beat on it to seat the rings, and get good compression. I've done > 100k miles in many of my cars and kicked the nuts off them from new. None have ever used a drop of oil. It's more about regular oil changes and oil quality than how you drive it.

Plenty of motorway miles only rep mobile diesels on 20k service intervals having major failures on our fleet over the last few years, which is why my sales guys are told to do no more than 10k between changes.

Enjoy the cars. Beat on them if you like. Whether it will fail or not is more about luck than how you treat it. And if you're in a 991, it's warenteed. For 3 years, and you'll likely trade it in before it runs out anyway.

Rockster

1,128 posts

46 months

[news] 
Saturday 6th October 2012 quote quote all
Scott Parker said:
No, this has to happen in the very first minutes of an engines life and that will happen on a bench at the factory
While the rings/bores develop some seal in the first few minutes of running proper break in takes longer.

Field and lab tests have found that break can continue for thousands of miles.

The new engine has a lot of friction and this creates heat and at higher engine speeds this heat can damage the engine.

Scored pistons/cylinder anyone?

My advice to the OP would be to follow the owners manual and at least at the end of break in unless forbidden by the owners manual do an oil/filter service.

With my 08 Cayman S I changed the oil/filter at 750 miles, again at around 1500 miles and then again at 2K miles just as the engine came out of "break in".

Sincerely,

Rockster.

REALIST123

3,739 posts

39 months

[news] 
Saturday 6th October 2012 quote quote all
wilkos said:
Am I the only one who finds this funny? If you have a new Porsche, then the chances of how you break it in having any effect on your life is minimal. You'll likely trade it in before the warrantee runs out, and the dealer won't ask "did you run it in" when he kicks you in the nuts with a trade value!

Enjoy the cars, drive how you want, and accept that you can be careful and crap happens, or you can enjoy it and crap may or may not still happen.

I am an engineer, and I'd say, let the fluids warm up, and then beat on it to seat the rings, and get good compression. I've done > 100k miles in many of my cars and kicked the nuts off them from new. None have ever used a drop of oil. It's more about regular oil changes and oil quality than how you drive it.

Plenty of motorway miles only rep mobile diesels on 20k service intervals having major failures on our fleet over the last few years, which is why my sales guys are told to do no more than 10k between changes.

Enjoy the cars. Beat on them if you like. Whether it will fail or not is more about luck than how you treat it. And if you're in a 991, it's warenteed. For 3 years, and you'll likely trade it in before it runs out anyway.
Interesting take from an 'engineer'. So you think it's just a matter of luck whether a sophisticated piece of mechanical engineering works properly or not, do you? Some engineer.

My 997 is now just over 5 years old, I've had it from new and it was run in properly. That took just a few weeks of that 5 years and the result is that I have an engine that runs as it should.

Maybe the problems your fleet suffers are more to do with your engineering skills than luck?
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