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My understanding of the bore scoring issue that sometimes occurs in these engines is primarily from going hard on a cold engine. Pistons get hot and expand fast when you stomp on the gas. Much more than the surrounding bore that will take far longer to get up to temp. Round peg gets too big for the round hole. While the bore scoring is an obvious and acute problem when it happens, I'm sure there are other things being damaged as well.

Enough said that an engine that isn't fully up to operating temp throughout won't have the correct design clearances and won't provide optimal lubrication. My BMW 330 convertible that is 226,000km and 21 years old has been warmed up before driving everytime. Cylinders are like new. Compression at new spec and leak down 2-3% on all. It hasn't been tracked but it definitely hasn't been babied.

My mantra is to change the fluids often and warm it up.
 

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Time has nothing to do with it. Its oil temp which is the lifeblood of the motor. 5-10 minutes in cold weather won't be anywhere near proper temp to push anything, and likely not even in warmer weather. All that matters is the oil temp. Not water temp or anything else as that will always be ahead of the oil temp. The engine is up to temp once the oil is at 180F/82C. Then and only then its perfectly safe to start really revving her out.

And never let the engine idle for long periods to warm up on cold start. That's a carryover from 50 years ago for old carbureted engines to wait for the over lean choke situation which could wash the oil from the cylinder walls when cold, yet for some reason many still think its a thing on modern cars. All of that is handled by the ECU now, so you want to immediately drive off to get the oil pressure up and get heat in the oil, and this is explicitly in the Porsche manual, but applies to any modern car for many years now
 

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I actually did some temperature testing and reported my findings on this thread: Foxwell NT530 - new user info and questions

As I found there, the oil is up to "final" temp in 3-6 minutes in cold weather. So while time isn't the ideal way to determine that the car is warmed up, the coolant gauge is reasonable (when it's up to temp, the oil is close enough to fully warmed, IMO). But even without the coolant temp gauge, 3-6 minutes is not a reasonable amount of time, even in cold weather... with just city driving (and shifts keeping below ~3k RPM).

I'm in full agreement that idling the car to warm it up is not a great idea. Start the car, wait a little if you want, and then drive off. Don't rev the hell out of it, and don't WOT during this time. That's what I'm seeing, and I've been doing that for years on all my cars with no ill effects.
 

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Field representatives used to WOT Lampredi twin overhead cams as soon as the car fired up, brand new not broken in cars. I was eighteen so I just shut up and passed the in-services but I always thought they were stupid for doing it. They wouldn't have done it at our shop.
 

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I actually did some temperature testing and reported my findings on this thread: Foxwell NT530 - new user info and questions

As I found there, the oil is up to "final" temp in 3-6 minutes in cold weather. So while time isn't the ideal way to determine that the car is warmed up, the coolant gauge is reasonable (when it's up to temp, the oil is close enough to fully warmed, IMO). But even without the coolant temp gauge, 3-6 minutes is not a reasonable amount of time, even in cold weather... with just city driving (and shifts keeping below ~3k RPM).

I'm in full agreement that idling the car to warm it up is not a great idea. Start the car, wait a little if you want, and then drive off. Don't rev the hell out of it, and don't WOT during this time. That's what I'm seeing, and I've been doing that for years on all my cars with no ill effects.
Oil fully up to temp after only 3 to 6 minutes from a cold start in the winter?

It’s in the mid 80s F where I live currently, and my oil temps are nowhere near up to temp in that amount of time, much less in the winter?

Are you saying that the readings from the OBD port is saying something completely different from what the gauge is telling us?

3 to 6 minutes after starting my car up in my garage only gets me down the street a few miles. My water temp isn’t even close to the final buffer 194F in that amount of time, much less the oil.

I don’t live in a cold climate, so winter temps average around 40 to 50F, but can get down near freezing. With 40 to 50, my oil temps in the cluster would only be showing about 80 to 100F after 3 to 6 minutes.

It will take at least 15 minutes or more and several miles of keeping the revs at 3000 RPM or less before I hit the 150 to 180 mark on the oil.
 

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Yes, it warmed up in that time, in the cold winter. I was surprised as well. The dash gauge basically agreed with the Foxwell readings - except that we know that the dash gauge is "processed" by the ECU. For example, the gauge stays at 175 on the dash even if you go over 84C... because they don't seem to want to "scare" users (as I recall, I've seen 90+C on the Foxwell at one point, but the dash stayed right on the "175" mark). This processing is also the same reason that when the coolant level is low, the temp gauge drops to "0" even though that's not correct/true either. Basically, the gauge is an "interpretation" of actual temperature, tweaked by whatever Porsche wanted to do in the background. In other words, that gauge is also not "connected" directly to the sensor.

These (warmer) days, I regularly see my temp at about the second bar (150F if you believe they are evenly spaced and divided numerically) by the time I get to the highway (5 minute drive, 1.9m according to Google)...

I'm happy to collect hard-data again, if there's something specific you want to see...
 

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Thanks for the follow-up! I'll have to pay more attention to mine and run a few experiments myself, as my Cobb device can show up to 6 different gauges from the OBD in real time, with a very long list of items watch or log. If I recall, I already have it set with the PDK temp and oil temp along with a few others, so time to drag it out and see what I can learn
 

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I dug around in my photos and found some detail. Dec 30, 2021 I went for a quick trip to pick up some takeout (I believe this was mentioned on my original thread mentioned above). This was city-speed driving the entire way... and I kept the revs low since it was warming up, of course.

Google Timeline says I left the house at 6:25pm (I'm not showing that here, as I don't want to give away my home address, haha). For the rest of this post, I'm going to stick to reporting times from the phone, as these are correlated versus the one on the dash which I don't adjiust as accurately/often (Google timeline and photos would likely use the same clock on the phone, after all, which is synced better than the car). I then took pictures of the dashboard while collecting data with the Foxwell. I won't go into the Foxwell data here (I believe I still have it if someone is interested) but I wanted to reference the pictures, as they tell the story well (especially since the Foxwell doesn't timestamp its data).

At 6:28 according to the photo, my dash showed 125F and an outside temp of 44F:
Watch Automotive lighting Speedometer Gauge Odometer


At 6:30, I took another picture. Temp is now at ~150F:
Speedometer Automotive lighting Gauge Trip computer Vehicle


I took a final picture when the temp hit 175F on the dash (at 6:32pm):
Speedometer Trip computer Odometer Gauge Tachometer


Net time is from 6:25pm to 6:32pm = 7 minutes. Outside temp 44F as seen on the dash photos.

Yes, oil temp lags this by a little... in my previous thread I found this was about 6 or 8 minutes (for my two test results). However, as I mentioned there as well, I contend that you don't need to go to fully-warmed on the temperatures (ie "stabilized" temps) because the oil viscosity "knees" over in the data at a much lower temp. Based on that, I consider my car is warmed up when the coolant is at temp. (I, personally, am happy even before that... I generally consider I'm fine at the 150F mark, but I'll wait a bit more if I can.)

In the end, my car "fully" warms up in 7 minutes (+/- 1 minute since we don't have seconds-display here), even in colder weather. This matches what I said before, where my 5 minute drive to the highway brings me just below the 2nd (150F) mark, where I still consider the car warm enough (and, if needed, I'll WOT as I merge onto the highway without concern).
 

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Oh, so you have been talking about water temp at 3-6 minutes? Yes, my water temp will come up much quicker, but its always way ahead of the oil gauge, especially in cooler weather on my 981. I know this because I have PSE, and an anecdotal observation is that the loud pops & crackles wont start occurring on throttle lift until my digital water temp hits 176F, regardless of sport mode being on or not. Right about that point is when my digital oil gauge is showing around 100F on the oil, and keep in mind the 981 oil temp logic is different between normal and sport modes, with sport running much lower than normal so staying in normal will heat it up faster. I cant recall if my previous 987 was the same though as its been 9 years since I had a 987?

But you have still inspired me to collect some OBD data on my 981 just to see now. I see yours is a 987, but I cant imagine that would make much difference since the S is similar motor depending on year, unless there is something fundamentally different between the plumbing and heat exchange setup on my 981?

I'll see what I can do this weekend during a morning drive, but the morning temps are already 60F so no chance to reproduce your test exactly. I did see a post over on Rennlist a couple years ago where a guy did some extensive logging along with physical oil examination equipment, and it was determined that 150F on the oil was about the safest early time to romp on it as the oil was operating at about 98% of the fully warmed up temp of 180F by that time.
 

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Yes, the data above was water temp, but as I said, in the other thread I correlated that to oil temp. As I said above, yes the oil temp lags coolant temp, but not by enough to worry about since the "normal" coolant temp is well past the "knee" of the viscosity curve for the oil anyway. Again, I provided some data in the other thread, but I can show you more info if desired - just need to know what you are looking for.

Yes, mine is a 987.2 (2010 Boxster base).

I would certainly love to see what you find out as well... no rush. Even 60F temperatures are useful info, generally speaking... so don't discount that. Data is good! :)
 

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Hi Schwinn, I was able to grab some down and dirty basic data toady like you did for some baseline values on my 981. I wanted to also run a log of the water and oil on my Cobb device to see what amount of buffering is going on between the OBD and what the gauge says, but was running late and didn't have time to drag it out and connect, so this is a good start for now.

8:04 AM. So image one is the cold start right of my garage with the oil and water essentially ambient at 70F/21C. The temp was actually 66 outside, but that will have no effect here so, I'm calling 70 for the start. I immediately backed out after the start and started driving shifting no higher than 3K in normal mode so the oil temp would come up the fastest
Speedometer Car Vehicle Gauge Automotive design


8:10AM. The next image was taken 6 minutes later and the water is up to 169F/76C and the oil is lagging way behind at 91F/33C
Car Speedometer Odometer Motor vehicle Gauge


8:14AM. The third pic was taken when the water first hit its final buffered values of 194F/90C and the oil had also crossed my minimum threshold for raising the RPMs up now to the 4-5K range, 10 minutes after start

Automotive tire Automotive lighting Motor vehicle Automotive design Car


8:16AM. The final image was when the oil crossed into the its fully up to temp value of 180F/82C.

Vehicle Car Automotive design Gadget Personal luxury car


So in summary, 10 minutes to the oil safe zone for starting to get more aggressive, and then 12 minutes to fully up to temp oil, however my starting ambient oil temp of 70F was much higher than your starting point, so this is exactly what I'm used to in winter months where it will take 15 minutes or more for the oil to heat. Starting out immediately in Sport modes may take even longer, as the 981 has different oil cooling logic in those modes to restrict its temp

It was a fun experiment, so thanks for the encouragement to play around with it a little bit today :)
 

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You blokes might be interested in this. A couple of years ago I was exploring PIWIS and comparing what you got on the MFD compared to the actual data the control units were detecting. I took a bunch of progressive screen grabs of data during a warmup from a cold start. It was at idle for most this, and from memory I started driving once the coolant got to 90. From what I observed the PDK gear oil cooling valve opens when the coolant temp gets to about 90, but warming/cooling of this fluid only happens properly once you drive the car due this being what turns the gear oil pump.

It's a small snapshot but it shows some quirks of the system.

From what I could see the coolant temp you see on the MFD isn't what the ECU is actually detecting. It seems to indicate a slightly higher value. Also, when it gets to 90C, it sits here even though the actual temp is fluctuating considerably. This isn't shown in the screen grabs but I've definitely observed this. The coolant temp needs to get to about 110C before it will show above 90C on the MFD.

The oil temp seems to be a filtered indication of all three oil temps, this being for a PDK. No idea what the manual gives you.

The PDK clutch fluid and engine oil rise at about the same rate and lag the coolant temp (MFD) by 20-25C due to the coolant warming both these fluids.

The screen grabs also show what the coolant valves on the PDK are doing.

Title above each images are the temps that were shown on the MFD at the time of the screen grab.

Coolant 70, Oil 25
Rectangle Font Material property Parallel Circle


Coolant 78, Oil 33
Rectangle Font Parallel Circle Number


Coolant 86, Oil 45
Rectangle Font Parallel Circle Number


Coolant 90, Oil 53
Rectangle Font Parallel Number Circle



Coolant 90, Oil 65
Rectangle Font Parallel Circle Number


Coolant 90, Oil 83
Rectangle Font Line Parallel Circle


Coolant 90, Oil 90
Rectangle Font Parallel Circle Number
 

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Yep, its well known that the 981 final coolant temp always locks to 194F/90C just like you see in my images above, despite actually being hotter than that. And as you noted, it will only change once a certain threshold is exceeded. I often wonder what that value is, so now we know from your data that its 230F/110C, so thanks for that! I guess Porsche thinks too many people will freak out seeing the water temps near or over 200F, so they buffer it with that fake 194F stop?

Mine is a PDK car, and I had also heard that the oil temp shown on the instruments is an average of the oil and PDK fluid temps, so good to know that this is accurate

As with anything Porsche, it's complicated like everything else. I just keep things simple and use my minimum oil temp threshold of 150F before starting to raise the RPMs above 3K, and then consider it fully warmed up by 180F, and then I'm comfortable redlining it.
 
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