Help on this DME report please!
#16
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I find it hard to believe that the rev limiter can stop the rpm's at exactly the cutoff rpm especially when the engine is moving up through its rpm band aggressively. Here's what Scott Slauson, PCA Technical Expert, has said:
"Ranges 1-3 are just 200 RPM's apart in a spread for each range just for mainly info on how you are bumping the rev limiter. Ranges 1-3 are common for just winding up to the rev limiter at 7200 , inertia will generate up to range 3 at this time. This will depend on your driving."
Also, I'm not sure I understand what you're saying about the overrev ignition counter - if it is not cumulative wouldn't it always report the same number, what your tech called "the maximum for a single event"? I know that's not the case since I regularly check my DME with a Durametric and over time I have seen increments in range 1 overrevs.
I always find DME readouts an interesting topic since there does seem to be a lot of confusion and mis-information. I'm not a Porsche tecn nor an engineer so I could be completely wrong here but this is what I've been told and have read over the last 7 years.
"Ranges 1-3 are just 200 RPM's apart in a spread for each range just for mainly info on how you are bumping the rev limiter. Ranges 1-3 are common for just winding up to the rev limiter at 7200 , inertia will generate up to range 3 at this time. This will depend on your driving."
Also, I'm not sure I understand what you're saying about the overrev ignition counter - if it is not cumulative wouldn't it always report the same number, what your tech called "the maximum for a single event"? I know that's not the case since I regularly check my DME with a Durametric and over time I have seen increments in range 1 overrevs.
I always find DME readouts an interesting topic since there does seem to be a lot of confusion and mis-information. I'm not a Porsche tecn nor an engineer so I could be completely wrong here but this is what I've been told and have read over the last 7 years.
Also, if the rev limiter function were instantaneous, there would never be any over revs, EXCEPT for missed shifts. That is simply not the case, as quoted d above in the statement from Scott Slauson, PCA Technical Expert.
Now let's discuss the cars with PDK. Many here believe that PDK cars will never have any over revs in any of the rev ranges. If a manual transmission car, when it bumps into the rev limiter, will show some over revs in ranges 1 ,2 and possibly 3, then what makes anyone think that a car Will PDK will not record similar over revs in Ranges 1, 2 and possibly 3? I believe that there are plenty of PDK cars with over revs in the lower rev ranges.
A PDK transmission car will not allow over revs caused by a missed shift, because the shift program will not allow a down shift if doing so will cause a mechanical over rev. I believe many here have misunderstood or misinterpreted the fact that PDK will not allow a mechanical over rev to also mean that PDK can never have an over rev. I believe if the rev limited has been hit during acceleration on a PDK car, there WILL be over revs in the lower ranges. If I had a PDK car, I would go out and bang off the rev limiter half a dozen times and then take it to the dealer for a DME readout and post it here for all to see, so we could prove that the world really is round.
Any owner of a PDK ever bounced of the rev limiter? If so, would you be willing to have your DME read by a Porsche dealer? If your dealer wants to charge you for the readout, I'll pay for it. If I have to pay to prove that my belief (theory) is wrong, then so be it, but it may also prove that a PDK can have over revs, and if so, then so be it, too.
#17
Interesting question, can you over rev a car with PDK by downshifting in manual. Will it disengage or not ?
When test driving my car I'm sure I down shifted in manual and bounced off the rev limiter. This may of triggered an over rev, who knows ? Damn toggle buttons are a pain and are going to take a bit of getting used to.
I may finally change to the paddle steering wheel, right up, left down.
When test driving my car I'm sure I down shifted in manual and bounced off the rev limiter. This may of triggered an over rev, who knows ? Damn toggle buttons are a pain and are going to take a bit of getting used to.
I may finally change to the paddle steering wheel, right up, left down.
#18
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I bounced my Cayman S with PDK off the rev limiter more than once. I had it read out and can't remember if I had any hits in range 1. I do know that I did not have any in range 2 and above.
#19
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Interesting question, can you over rev a car with PDK by downshifting in manual. Will it disengage or not ?
When test driving my car I'm sure I down shifted in manual and bounced off the rev limiter. This may of triggered an over rev, who knows ? Damn toggle buttons are a pain and are going to take a bit of getting used to.
I may finally change to the paddle steering wheel, right up, left down.
When test driving my car I'm sure I down shifted in manual and bounced off the rev limiter. This may of triggered an over rev, who knows ? Damn toggle buttons are a pain and are going to take a bit of getting used to.
I may finally change to the paddle steering wheel, right up, left down.
#21
Unless the report has changed in the last few years, it's a cumulative report of the number of ignitions in the various ranges. Anything above 3 is likely to cause engine damage. It is very likely that a range 1 was caused by the rev limiter intervention, so it's unlikely that the event lasted more than about .5 second. That would account for a little over 90 ignitions or 180 if it were a full second in that range, very unlikely. 6K+ in range 1is not one event.
#22
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Resurrecting thread for report I received today:
Range 1 - 2262 (to 7500 rpm)
Range 2 - 231 (to 7700 rpm)
Range 3 - 24 - (to 7900 rpm)
The service manager at the dealership told me this was fine and nothing to worry about. He said it was one of the cleanest reports he's seen. I was hoping to not see any in Range 2 and above. Without the info about the hours, etc. when these occurred, what comfort or fear should these numbers give me?
Range 1 - 2262 (to 7500 rpm)
Range 2 - 231 (to 7700 rpm)
Range 3 - 24 - (to 7900 rpm)
The service manager at the dealership told me this was fine and nothing to worry about. He said it was one of the cleanest reports he's seen. I was hoping to not see any in Range 2 and above. Without the info about the hours, etc. when these occurred, what comfort or fear should these numbers give me?
#23
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I can update on my experience with an 11 GTS with PDK. I did get hits in range 1 and 2 when bouncing off the rev limiter in manual.
As to you DME readout I wouldn't worry about it. Divide the numbers in the ranges by 3 and that's the number of rpms in that range.
As to you DME readout I wouldn't worry about it. Divide the numbers in the ranges by 3 and that's the number of rpms in that range.
#24
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Would you please post the numbers? Better yet, start a new thread with the title "Over revs on my GTS with PDK" something similar.
Ever since the PDK came out in 2009, my contention has been that one CAN have acceleration over revs with a PDK, while most here have said that is impossible.
Many were mistaking the apparent inability of PDK to induce a "money shift" over rev when downshifting to mean that it was impossible to have ANY over revs on a PDK car.
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Resurrecting thread for report I received today:
Range 1 - 2262 (to 7500 rpm)
Range 2 - 231 (to 7700 rpm)
Range 3 - 24 - (to 7900 rpm)
The service manager at the dealership told me this was fine and nothing to worry about. He said it was one of the cleanest reports he's seen. I was hoping to not see any in Range 2 and above. Without the info about the hours, etc. when these occurred, what comfort or fear should these numbers give me?
Range 1 - 2262 (to 7500 rpm)
Range 2 - 231 (to 7700 rpm)
Range 3 - 24 - (to 7900 rpm)
The service manager at the dealership told me this was fine and nothing to worry about. He said it was one of the cleanest reports he's seen. I was hoping to not see any in Range 2 and above. Without the info about the hours, etc. when these occurred, what comfort or fear should these numbers give me?
The range 1 & 2 numbers are competely normal. Range 3 numbers are suspect and a gray area. Your range 4-6 numbers are missing and very-very valid/necessary.
If this is a PPI report, I'd pass.
#26
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Where's MacMaster on this thread ??
Ranges 1-3 are generally regarded as acceptable. There are plenty of cars that only have range 1-2, but I would also look at 'when' the upper ranges happened.
I just don't think cars with even Range 4 are considered hopeless, once again look at when it happened and check the car for any indications of damage. If the rev happened 20K miles ago that gave it a range 3 or 4, and the engine checks out clean otherwise, I wouldn't pass because of a short hit in those ranges.
Ranges 1-3 are generally regarded as acceptable. There are plenty of cars that only have range 1-2, but I would also look at 'when' the upper ranges happened.
I just don't think cars with even Range 4 are considered hopeless, once again look at when it happened and check the car for any indications of damage. If the rev happened 20K miles ago that gave it a range 3 or 4, and the engine checks out clean otherwise, I wouldn't pass because of a short hit in those ranges.
#27
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Alan,
Would you please post the numbers? Better yet, start a new thread with the title "Over revs on my GTS with PDK" something similar.
Ever since the PDK came out in 2009, my contention has been that one CAN have acceleration over revs with a PDK, while most here have said that is impossible.
Many were mistaking the apparent inability of PDK to induce a "money shift" over rev when downshifting to mean that it was impossible to have ANY over revs on a PDK car.
Would you please post the numbers? Better yet, start a new thread with the title "Over revs on my GTS with PDK" something similar.
Ever since the PDK came out in 2009, my contention has been that one CAN have acceleration over revs with a PDK, while most here have said that is impossible.
Many were mistaking the apparent inability of PDK to induce a "money shift" over rev when downshifting to mean that it was impossible to have ANY over revs on a PDK car.
Also watched my Indy pull some DME's with his Duramatic on some PDK's. All research lead me to the conclusion anything above a 1 on a PDK is literally impossible.
Service manager in FL stated that a freak incident of getting a rear wheel off the ground (say in a corner on the track) while accelerating is the only conceivable way.
#28
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I'll post a new thread titled '2011 GTS PDK DME Rev Ranges Observed' with a screen shot.
Last edited by Alan C.; 05-18-2012 at 01:45 AM.
#30
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If you do the math and divide the numbers by 3 it is meaningless to me. I purchased an 09 C2S with a very similar reading and the car was CPO. Good to see that there were no hits in 4-5-6.