Over revs

[BBB]

Ever since I read about Porsches storing every occasion that the engine is over revved, in the ECU, I’ve wanted to have a look at the data in mine. I finally got around to it today.

For those unfamiliar with what the information means, this is a great link.

https://911virgin.com/engine-revs/

My results

Range 1, 6274 ignitions, last report at 2123 hours of run time

Range 2, 248 at 1432 hours

Range 3, 2 at 1108 hours

 Nothing in ranges 4 to 6  (thankfully).

Total run hours = 2480 hours. 

Range 1 is revs in the range 7200 - 7500, and doing the maths shows that there have been a total of 17.4 seconds in the engine’s history when the engine was in this range, the last report was 356 hours of run time ago, so during my ownership.

Range 2 is revs in the range 7500 - 7700, maths again shows 0.66 seconds, about a thousand hours ago

Range 3, with only 2 ignitions is 5 milliseconds and to be ignored if the link above is true (they say to ignore less than 10 ignitions).

Interesting to read that ranges 1 and 2 are not an issue, so overall I’m happy and relieved with the data. It’s also something that I would check when buying a Porsche in the future. For info, this was read using a Foxwell NT 510 Pro scanner that I got second hand for £80 off ebay. 

[iborguk]

23 minutes ago, BBB said:

Ever since I read about Porsches storing every occasion that the engine is over revved, in the ECU, I’ve wanted to have a look at the data in mine. I finally got around to it today.

For those unfamiliar with what the information means, this is a great link.

https://911virgin.com/engine-revs/

My results

Range 1, 6274 ignitions, last report at 2123 hours of run time

Range 2, 248 at 1432 hours

Range 3, 2 at 1108 hours

 Nothing in ranges 4 to 6  (thankfully).

Total run hours = 2480 hours. 

Range 1 is revs in the range 7200 - 7500, and doing the maths shows that there have been a total of 17.4 seconds in the engine’s history when the engine was in this range, the last report was 356 hours of run time ago, so during my ownership.

Range 2 is revs in the range 7500 - 7700, maths again shows 0.66 seconds, about a thousand hours ago

Range 3, with only 2 ignitions is 5 milliseconds and to be ignored if the link above is true (they say to ignore less than 10 ignitions).

Interesting to read that ranges 1 and 2 are not an issue, so overall I’m happy and relieved with the data. It’s also something that I would check when buying a Porsche in the future. For info, this was read using a Foxwell NT 510 Pro scanner that I got second hand for £80 off ebay. 

Yup good to read those as part of pre-purchase as you say, certainly on a Manual.

Edited February 25, 2023 by iborguk

[brillomaster]

Whats the rev limit of your car? Guessing 7500rpm?

Wonder what mine has done now... 4 trackdays done, which obviously involves frequent trips to the redline...

[BBB]

1 hour ago, brillomaster said:

Whats the rev limit of your car? Guessing 7500rpm?

Wonder what mine has done now... 4 trackdays done, which obviously involves frequent trips to the redline...

Trips to the redline are fine. From what I can tell, the damage occurs when circumstances occur which take the engine past what the ECU can control, so called over revs.

[entdgc]

39 minutes ago, BBB said:

Trips to the redline are fine. From what I can tell, the damage occurs when circumstances occur which take the engine past what the ECU can control, so called over revs.

I thought the normal cause was downshifting too quickly? As during acceleration the rev limiter would stop it?

[BBB]

15 minutes ago, entdgc said:

I thought the normal cause was downshifting too quickly? As during acceleration the rev limiter would stop it?

Yes, that would do it, as you say, the rev limiter normally catches it. Another example is in the link.

Whilst on a final blast before attempting to sell to ourselves, a moment of indiscretion racing a group of motorbikes saw the limiter exceeded whilst at full throttle down a long steep hill. The incline caused the car to travel faster than it otherwise would have done, the cars momentum taking the engine past its limiter damaging it in the process.