6 ignitions divided by 3 ignitions per revolution means that the engine rotated 2 revolutions. 2 revolutions divided by 10085 revolutions /min the whole thing times 60 sec/min = .01 seconds. Not much.

But it only takes one revolution to destroy a valve.

 

I think 6 ignitions is 2 revolutions, so very briefly above 10k but would take a little time to spin down below 9k.

 

Well, luckily there was no such damage! At what RPM is there a guarantee that a valve gets smashed?

 

There is no certain threshold. It depends how well the particular valve spring controls the motion of the valve and prevents contact with the piston.

 

991.2

 

Thanks Grant so even if the needle keeps rising there is no internal momentum on the motor mechanic?

Have you ever heard of the ignition shutting off on hitting the limiter hard? Happened out of the hairpin at Sonoma twice on me - odd. Had to turn the key on again.

Chris

 

No, there is inertia to keep everything turning but it doesn’t accelerate without adding force.

 

I stopped by my local Porsche dealership to get a copy of my DME report just out of curiosity because I have been driving my car pretty hard since break-in.

There are only three over-rev ranges on the 992 GT3. I had 26 ignitions on range one which occurred 20 operating hours ago so that was several track events back for me. (I am not sure how I did this as I don't specifically recall it - but oops)

Range 1 must not be triggered by bouncing off the rev limiter because I did that last weekend at the track inadvertently and it did not show up as an over rev. I also attached the entire technical printout from PIWIS which is very interesting. Part 1 is here. DME report is on page 7 of the attached. but I screenshotted it here in case you don't want to open up the whole document.

 

Here is part 2 of the the technical printout from PIWIS. It's 90 pages total.

 

Thanks! Were you able to confirm that Range 1 only starts at 9,600 rpm now as previously reported? Did you find the definitions of Ranges 1, 2, and 3 and the Max RPM that you hit?

Much appreciated,
Grant

 

The DME report for my 991.2 GT cars shows max engine speed, etc. That info should be in there?

 

I don't see a lot of the info from typical DME reports listed in this doc.

 

I didn't confirm anything really other than what is in the attached documents above. I did sit with the tech while he downloaded the report but I knew more about these DME reports than he did and he is their most experienced tech. (e.g., I had to correct him that the number was ignitions and not number of revolutions of the crank at that over-rev range). Actually, I spent most of my time talking to him about how to change the plugs in my 991.2 C4 which is a major pain in the butt and nothing really online about it.

I am a little suspicious about the 26 ignitions in range 1 that are shown because I know what track day that was. I was in the novice group and pushing the car but not really hard. and I don't remember any early down shifts or misshifts etc and there is no way I got up to 9600 rpms that day. Last week, I was in the intermediate group and really pushing myself and the car and nothing was recorded.

It is not there from what I can see. Only the time stamp of when the over rev occurred.

Yes, I agree. I believe this 90 page document was only a section of the total information/report. There were multiple tabs and he only printed out this one tab that included the over-revs.

 

I believe you - the DME over-rev counter has always been unreliable. In the 991.2, Range 1 began at 9,000 rpm and there were often false readings in this and higher ranges. It was seemingly the intent of Porsche to raise Range 1 to 9,600 rpm to reduce these erroneous reports - but apparently, it still hasn't solved the issue if you're pretty confident you never missed or hurried a shift.

 

Hi,

if like to chime in please. There appears to be some misinformation here. This is what I know to be true from PAG directly.

Porsche truncated the ranges from 1-6 from the 991.2 to 1-3 for the 992. They actually did this for the 991.1 but no one seemed to remember or notice.

Depsite what is being said, I know for a fact the 992 GT3 is as follows:

R1: 9001-9250
R2: 9251-9500
R3: 9500+

Porsche looks at 9501 the same as 10501, their thoughts are same as what Mooty said. It’s either broken or it’s not. In fact they actually had the thought of just R1 and R2, so it was soft or hard over rev, which in my personal view is probably better.

Procedure for R3 is same as before.

Scope
Compression
Oil analysis
Drive for 40 hours.

Can still CPO 992 GT3 with R3.

Bottom line is this. Don’t be afraid to buy or drive or sell a R3 car. If it drives and nothing appears wrong, it’s fine.