Thrashing at the Red Line - evidence???

When buying a newer 911 (eg 996 or 997) are there any tests which can be carried out at PPI stage to show if the car has been thrashed at the red line? - on a manual of course (not possible on a Tip) & if not, how would you know with any certainty how it has been driven??

If I'm not mistaken that data is available if it's connected to a machine able to read it (from centraline?).

I think you'll find it hard to find a 911 that hasn't been to the red line. It's the over-revving that would be more important I think. And I believe this information is available to those with the hardware/software to read the information from the ECU. i.e. an OPC for example.

I don't know if there is such a test to show how much redlining a car has endured. The engines do have rev limiters which hopefully is an indication that its o.k.ish to red line them and hopefully the cutout is at a point well within the engines design perameters. I think for me the more important issue is how sympathetically the engine has been treated during the warm up stages of use from cold starts and how many stop start short journeys the car has had. Don't know if there is a test for that either!

On 996's two rev ranges are recorded in the DME Vehicle data. Range 1 is the number of ignitions that the engine has made as it hits the electronic rev limiter. Range 2 is the number of ignitions above that, usually caused by a premature downshift. It also records the time of the last occurrence Remember, these are numbers of ignitions, and there are 2 ignitions per revolution. The attached figures are from an X51 Turbo I checked for someone recently. This was with a PIWIS tester, but I believe the Durametric software also shows this data. You can see that this car has only had one micro-buzz, so nothing to worry about. Different models have different recorded ranges, and the 987/997 series record more ranges as follows: Boxster 986 RANGE 1, 7200-7800 RANGE 2, 7800 and up 996 RANGE 1, 7300-7900 RANGE 2, 7900 up 996TT RANGE 1, 6750-7250 RANGE 2, 7250 up 996 GT3 RANGE 1, 8200-8800 RANGE 2, 8800 up Carrera GT RANGE 1, 8400-9000 RANGE 2, 9000 up 987 Boxster RANGE 1, 7200-7500 RANGE 2, 7500-7700 RANGE 3, 7700-7900 RANGE 4, 7900-8400 RANGE 5, 8400-9500 RANGE 6, 9500 up 997 Carrera RANGE 1, 7300-7500 RANGE 2, 7500-7700 RANGE 3, 7700-7900 RANGE 4, 7900-8400 RANGE 5, 8400-9500 RANGE 6, 9500 up 997 GT3 RANGE 1, 9000-9200 RANGE 2, 9200-9400 RANGE 3, 9400-9600 RANGE 4, 9600-10000 RANGE 5, 10000-11000 RANGE 6, 11000 up 997TT RANGE 1, 6800-7000 RANGE 2, 7000-7200 RANGE 3, 7200-7400 RANGE 4, 7400-7900 RANGE 5, 7900-9000 RANGE 6, 9000 up

Why would it matter? Surely the overall condition + history would be more important than hitting the rev limiter? I drive my 911 hard every every day i drive it and it's maintained regardless so it makes no odds. They are designed to do it so don't worry.

It's not hitting the rev limiter that's the problem. It's continuous severe over-rev conditions that can cause damage which might surface in later life. It also shows the car has been abused.

Really don't see your point fella sorry but i think it's a daft question to ask :dont know: If the car has been bouncing off the limiter most of it's life it will show in the condition of the car. There is no such thing as a mint car which has had the nuts thrashed off it.

There is no problem with driving the car hard, if it is done with some sympathy for the mechanics of the machine. If you abuse it by changing down too early you could force the engine to rev at, say, 10-11000 rpm, which it was not designed to do. It would put huge loads on the connecting rods and bearings, valve train, gearbox, clutch, etc, and that might do long term damage, shortening the life of the engine and drive train, or even causing a premature failure. I take your point, but mechanical abuse wouldn't necessarily show up in the paintwork. Just my tuppence worth, but I feel it was a legitimate question for the OP to ask.

Richard you are correct in your thoughts the Durametric shows the information identical to what you have mentioned on PIWIS. IMO it would be difficult to suss out whether the car had been thrashed or used properley by looking at the data held within the DME. For instance, it had shown that over the past few weeks I had over-revved but I honestly can not think of a single point of even Red-lining the car let alone hitting the fuel-cut etc. So, if the car was driven by me on a daily commute for 6 months it would look thrashed on the data but the truth is it was driven normally. What do you think?

I think you can only consider the average of the results, and make an informed judgement based on them. The TT data above shows 9900 Range 1 ignitions, or 3300 revolutions, and at 6000 rpm that represents 33 seconds. If you took each incidence of reaching that rev range as 0.5 seconds, it means that it has happened 66 times in the car's life. In 1000 hours of running, I'd say the car had been driven very carefully/sympathetically. One of the things I meant about mechanical sympathy is not constantly bouncing it off the rev limiter. There is little point in doing it, because it slows down progress. On a TT (for example), peak power is between 5500 and 6700 rpm. Peak torque drops off at 5000 rpm. You will get quicker acceleration times by changing just before the limiter cuts in - not just after.

I am 100% with you on the Richard, you can actually feel the engine peak power dropping shortly after 5500rpm so any rev's above 6k are pointless. Back on topic, I reckon even if you did get a printout of the over-revs you wouldn't be able to really pull the desired info from it. Just go by what the car starts and drives like, ensure you take your test drive from stone cold so you can drive through the whole warm up process. Don't forget these engines were designed to handle the rev's that the DME allows and perhaps several more.