autobonrun

Manimal, I've always been a bit hesitant to voice an opinion on these over rev reports because there are so many threads on the subject. I look at the rev counts on the printouts as data, not information. There's a big difference. Advances in technology have inundated the world with data but substantially less information. However, I understand why many in the market for a TT try to interpret the reports. When you drop $50k+ on a car, you try to find some "information" that the heart of the car is strong. However trying to determine information from these reports is like trying to read an EKG chart; lots of data but maybe only one of the spikes means anything; and it's highly likely to be misinterpreted by the partially trained. Porsche should just include the software in the ECU to do this interpretation for the layperson; should have been easy to do. Just indicate if a mechanical over rev was detected.

The reason I asked in an earlier post which Porsche was the first to offer these over rev reports is that I was curious what the individuals that purchase 930, 964, and 993 turbos do without the reports. Not surprisingly, the cars survive and I don't read anything about engines being replaced due to non-detected over revs; not that engines don't blow. It just doesn't appear to me the risk with the older turbos is any greater because of the lack of over rev reports. My opinion (and that's all it is) is that you can safely buy a newer turbo without over analyzing a rev report if you perform other PPI and due diligence. Like everything in life, there's always some risk.

My preference would be for a report that just told me how far over red line (due to mechanical over-rev) the engine experienced, how long it stayed there, and how long ago it occurred. Don't give me all this ignition count stuff that I need to convert and interpret. Humans think in seconds, not ignition counts. And I don't need to know it bumped off redline at some point in the last 20 years. I've bumped my SC off redline for over 30 years; same engine, never opened, 215k miles. The TT engine is just as robust.

IMO

pfbz

The ECU rev range data was never intended for public dissemination and interpretation.


But yes, the 1) different trigger points between models, the 2) poor choice of trigger points for the 996 Turbo cars, 3) differing number of ranges between generations, the 4) counts being in units that aren't intuitive, the 5) hard limit on number of events each range can detect, and the 6) known issues with spurious, impossible data sometimes being recorded makes rev range data subject to frequent misinterpretation by buyers, PARTICULARLY on our 996 Turbos.

On top of it all, there are shops with tools that can alter/erase rev range data, though that seems to be a problem on the resale the high-buck GT models, not our lowly Turbos.

T10Chris

This, It was for Porsche to monitor for "abuse" while the cars were under warranty or before authorizing a used car as CPO.

autobonrun

I think you and pfbz just nailed the real issue. But since the public now knows the information is available, and has access, how do you prevent the layperson from trying to interpret it. I say produce something simple and easy to understand, and keep this over rev report with the mechanics. If you are provided the output from an MRI or Xray, you depend on the doctor to interpret it for you. You don't try to do it yourself. Seems similar to me.

flyn2001

2fcknfst

+1 - I see the range 2 tabs on various drop downs, just open them up?