DME results from my PPI, I need help!

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Jul 17, 2009 | 08:46 AM
  #31  
Since this is a hot thread, i thought I'd throw out this question: Does anyone know if the DME range report is cummulative, i.e. if you have an ignition in Range 2, you will also have an ignition in Range 1 since it needed to go through that range first? Or if you have a recording in 2, it does not include the time in Range 1 the motor spent on the way to 2? Seems like it would need to record time in any of the lower zones as well.
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Jul 17, 2009 | 08:50 AM
  #32  
Quote: Since this is a hot thread, i thought I'd throw out this question: Does anyone know if the DME range report is cummulative, i.e. if you have an ignition in Range 2, you will also have an ignition in Range 1 since it needed to go through that range first? Or if you have a recording in 2, it does not include the time in Range 1 the motor spent on the way to 2? Seems like it would need to record time in any of the lower zones as well.
Absolutely - it would need to record time in any of the lower zones as well. I can't imagine it any other way.

The computer just records that there was an ignition at a certain RPM. It doesn't know whether you are going up or down or whatever. It just notes what it sees. You get to do the interpreting.
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Jul 17, 2009 | 12:21 PM
  #33  
Quote: Since this is a hot thread, i thought I'd throw out this question: Does anyone know if the DME range report is cummulative, i.e. if you have an ignition in Range 2, you will also have an ignition in Range 1 since it needed to go through that range first? Or if you have a recording in 2, it does not include the time in Range 1 the motor spent on the way to 2? Seems like it would need to record time in any of the lower zones as well.
And the engine hour info indicates the last operating hour that this range occured in.
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Jul 17, 2009 | 01:09 PM
  #34  
To add a question to this discussion...

Can a porsche dealer CPO a car that has stage 4, 5, or 6 over-revs? Where does Porsche draw the line on CPO eligibility? Stage 1? Stage 2? Stage 3? I would assume a stage 5 or 6 would make the car ineligible for CPO status.

So would I be safe to assume that a car offered for sale at a porsche dealer as a CPO car has a clean DME scan? I'll still ask for the printout to make sure, but I'm just wondering if there is a policy on this.
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Jul 17, 2009 | 03:03 PM
  #35  
Quote: No...47214 is the number of ignitions. There are 350 ignitions per second at 7000RPM...134 seconds.
Could someone walk me through the math on this... I'm apparently brain-dead today.

How do you get from 7000 RPM to 350 ignitions?

7000 RPM is 116.67 Revs per second.

The engine is 2 banks of 3 cylinders each, with an ignition in each cylinder.

If one assumes 116.67 x 3 cylinders one does get 350, but the other 3 cylinders are also igniting on each revolution, right? Are not all 6 cylinders lighting each revolution?

Should it not be 116.67 x 6 = 700 ignitions per second at 7000 RPM ?


With that DME readout I'd be concerned too. But one could also look at it this way. With the engine having been driven that hard and for that many miles, I'd say if the mechanic finds no leaks and issues, the engine would be good as the miles and revs would have brought to the forefront any issues. An engine that has not been pushed and only has 3000 miles on it, on the otherhand, may have manufacturing defects in it that are still undiscovered. That said, if it was my money, I'd be concerned a bit.
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Jul 17, 2009 | 03:06 PM
  #36  
After reading SOME (not the majority, but a decent number) of comments on other threads about how some folks don't have ANY concern for or effort toward longevity, and just routinely beat the crap out of their car, and how this car has CLEARLY been beat on, I wouldn't buy it, non CPO especially.
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Jul 17, 2009 | 03:15 PM
  #37  
Each cylinder only gets an ignition every other revolution of the crank. You're thinking of a 2 stroke engine, Porsches aren't lawn mowers

http://www.howstuffworks.com/engine.htm

Quote: Could someone walk me through the math on this... I'm apparently brain-dead today.

How do you get from 7000 RPM to 350 ignitions?
...
Should it not be 116.67 x 6 = 700 ignitions per second at 7000 RPM ?
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Jul 17, 2009 | 03:23 PM
  #38  
[QUOTE=JEllis;2465769]
Quote:
I am of the point of view that middle aged lawyer cars that have been babied and hardly ever see redline are the ones that tend to have issues. A redline a day keeps the mechanic away!

Jason
+1 I agree.

No matter what the DME reads, there are still these truths which remain:
-it is a USED car
-it is a Porsche sports car, designed to be driven hard, and most likely was
-most buyers are not Porsche master techs, and really can't interpret the DME scan with full accuracy
-there is no evidence that a car with less overrev ranges will have better longevity than another with more

If you want a car with no overrevs, buy a new one. All this misinterpretation of DME's and ties to resale value is ridiculous.

Its obvious most folks here buy and sell insurance as an occupation, more than you treat patients medically. If you were physicians, you'd be treating lab values, as opposed to treating the patient and their symptoms.

Buy the car and accept it for what it is: a used sports car that CAN handle spirited driving
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Jul 17, 2009 | 03:33 PM
  #39  
There is no definition of a clean DME scan, so to answer your question: yes your dealership can cpo a car with range 4,5,6. In fact, there's a cpo car at the local dealership that has a few range 4's and 5's on it.the Porsche techs mentioned that it happened over 75 hours ago, so the car warranty is still valid.

Quote: To add a question to this discussion...

Can a porsche dealer CPO a car that has stage 4, 5, or 6 over-revs? Where does Porsche draw the line on CPO eligibility? Stage 1? Stage 2? Stage 3? I would assume a stage 5 or 6 would make the car ineligible for CPO status.

So would I be safe to assume that a car offered for sale at a porsche dealer as a CPO car has a clean DME scan? I'll still ask for the printout to make sure, but I'm just wondering if there is a policy on this.
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Jul 17, 2009 | 03:34 PM
  #40  
[QUOTE=RiceEater;2466270]
Quote:
+1 I agree.

...

Buy the car and accept it for what it is: a used sports car that CAN handle spirited driving
Also accept that you will be denied warranty service when your spirited driven engine/transmission blows. It is exactly what I spoke about with service manager 2 days ago in regard to those DME scan numbers BTW.
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Jul 17, 2009 | 03:49 PM
  #41  
[QUOTE=utkinpol;2466280]
Quote:
Also accept that you will be denied warranty service when your spirited driven engine/transmission blows. It is exactly what I spoke about with service manager 2 days ago in regard to those DME scan numbers BTW.
The op already mentioned that the car in question has no warranty.

My service manager says the range 5 may be of concern if it's happened within 75 operating hours. If it happened a long time ago, he says the car is squeaky clean.

Btw, if these dme scans worry you, you guys better not buy any used GT3's. They all have some nice ranges on their DME scans.
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Jul 17, 2009 | 04:20 PM
  #42  
The feedback so far guys has been absolutely great! I sincerely appreciate the time everybody is taking formulating their responses. I feel like the only way I can truly make a final decision here is to identify the car. I actually wasn't planning on ID'ing the car, but I think it may help the discussion. Here is the car I'm considering with less than stellar DME overrev scan:

https://www.6speedonline.com/forums/...ack-betty.html

I know this car has been in the 6 Speed family and known well; So previous owners PLEASE weigh-in if you would. It is clearly a unique & special vehicle, so I'm having a really difficult time dismissing it because of the DME scan. I have paid for the PPI which came back clean and I LOVE the subtle mods and overall superb condition. The owner of this car has been absolutely fantastic and has spent a ton of time with me discussing the purchase.

Help me out guys! Now that you know which car I'm considering, I welcome any and all input. If I can get the car for a better price, does that offset the DME at all? Sorry to ramble on, I'm just trying to make the right decision as I join the Porsche family.

Thanks in advance!

Jay Jones
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Jul 17, 2009 | 04:42 PM
  #43  
I don't know the car but I think $60K (if that is still the price) is way too much. I own a pristine (IMHO) Launch Car as well (#337) w/ 17K miles and I'd take $60K (if I was selling it) in a heart beat.

I don't want to sour your deal or create a problem for the seller but I think it's my 6speedonline. com duty to offer up my opinion.
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Jul 17, 2009 | 04:50 PM
  #44  
AP 997S, the agreed upon price was 54K before the PPI and DME results.

Jay
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Jul 17, 2009 | 05:02 PM
  #45  
If you haven't already, have it checked out by a mechanic of your choice.

Otherwise, its obvious the car was tracked, which explains the DME. The car has lived thru spirited driving and will continue to do so.

As I mentioned in previous posts, the DME doesn't bother me as long as it makes sense with the history of the car.

If you are ok with the fact that it was tracked and are ok with the way the car feels after a test drive (e.g. No engine rumbles, good brakes, no squeaks), then go for it.

If you want a camry with good dme, there are plenty out there. If you want a Porsche that wasn't driven in a spirited fashion, look for another. Most cars on this board are owned by enthusiasts that actually drive their cars up to redline.

Buy it and enjoy it.
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