AudiOn19s

I don't think it works that way. I think you can change the rev limit but the over-rev counter still reads off the original 8200 number. I seem to remember this being a more common thing on ECU flashed Turbo's than GT3's. I'd be curious to know myself if changing the limiter in a tune also changes how the over-rev's count, but I don't think that it does.

Tom Loder

Thanks for the data point @mnwild

The car had a PPI done and this was the result of the scan. The ECU thought occurred after and now hoping they can test the rev limiter today to see if the car will stop or go past.

This car was used for PCA club racing since 2009. It is not street legal, so if you remove time spent idling in pits, and driving through the paddock, it has endured probably 5 hours of either qualifying, sprint races, or an enduro since the last range 2 event at 666.6 hours. I would like to think that if something bad was lurking it would’ve showed itself under that kind of stress. But maybe that is wishful thinking.

cgfen

perhaps something did in the resulting 6.6 hours and that's why it is now for sale?
I would be leery of a car with those type 2s so close to current operating time.

Olemiss540

A race car?!

I would bet there is a tune allowing for the non-mechanical overrevs. Compression and leakdown test would make me feel much better regardless of if there were 1 or 100 instances shown in the ECU.

ScottArizona

I agree with above two posters. And I also agree that if the redline has been increased it would give me a little more comfort because although over revs will still be logged it will be much easier to hit a zone 2 overrev if the rev limiter is not kicking in at the stock level. It just means that there was not necessarily a mechanical overrev, which is the scary kind. Problem here is that the last zone two was relatively recent. With that said if compression and leak down is good and the car drives well and the price reflects all the risks I’d say go for it in the car otherwise suits your fancy.

himself

Correct. It is the total Range 2. As I noted, there is no way to tell when those happened other than the last one happened approximately 6 hours ago. That is - there is a chance that ALL of them happened then. That's why I would be worried. *owner: "WHOA. Oops, that was a money shift. Time to sell the car"**

I also agree that an ECU mod shouldn't change how the Ranges are counted. The only issue is that you would see many more Range 1's.

I note some inconsistent discussions on the RPMs for Range 1 and Range 2. I was under the impression that Range 1 is over 8200, but below 8800. Range 2 is over 8800. That is:
996 GT3
RANGE 1, 8200-8800
RANGE 2, 8800 and over

I'm sure a math wiz can confirm this, but at 10,000 RPM = [10,000 / 60 *3 ignitions per rev] = 500 ignitions per second. 12,000 ignitions / 500 ignitions per second = 24 seconds -> that's a lot of time past 8800 RPM.

IMO, having 12,000+ Range 2 is objectively a lot. I figure most people start to get nervous when there are over 1-2 seconds of Range 2 [a thousand or so on the counter ]. That long and I'd be thinking money shift. 5 to 2 is usually the culprit. I mean, with the rev limiter, there's really no other way to mechanically get the engine to exceed 8800. Sure, a car could get a few Range 2 some other way, but over over 20 seconds of Range 2? I'd be VERY nervous.

-td

Igooz

The maximum count for each range is 65535, so there may be 70,000 or 700,000 or 7,000,000 million actual counts on range 1 but the counter cannot count anymore than 65,535.
Also, the 996 DME is trigger happy and it just counts. It has been a PITA and has caused discussions since 2001...

spiller

^^ This. Even on a 5-2 down shift there’s no way it’s one event. On a mis shift going up the gears say from 3-2 (instead of 4th) or 4-3 (instead of 5th) etc, you’ll blow into range 2 but likely only for a split second. 5-2 is the big one that usually accumulates ignitions as the car is already decelerating and the driver usually doesn’t realise what he’s done right away and so more difficult to avert the crisis. Still as above, I’m thinking multiple range 2 events, like 10+ events at 1-3 seconds each. If that’s the case, maybe it shows how stout these motors really are. Or it could be a fluffed ECU.

Tom Loder

I had the shop that did the PPI test the rev limiter and they found it to be working at the stock limit.

thanks for all the inputs. I have decided to pass on the car.

JJT

In the blog he explains it very well

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

mnwild

Good article, similar to what I read before but more detail. Gives me some peace of mind with my car.

@Tom Loder I think you made a wise choice to pass

Nickshu

Maybe this has already been said but there are documented 996's with ECU glitches that count range 1 overrevs as range 2. Also some that show swapped range 1 and 2 data. There is a thread on this around here somewhere.

jpoint

Since you're passing on the car it's a moot point but my GT3 has some minor bounces off the limiter in Range 2. When we were preparing to pull the engine for the coolant pipes I had a leak down and compression test at about 51k miles on the car and it came back at less than 1% across all the cylinders. The shop actually did the test twice because it just seemed impossible. These engines are pretty stout.

Tom Loder

interesting, thanks for sharing. I wouldn’t want to hope for a glitch as the cause. Is there a way to find out if it was a computer error or just owner testimony?

Nickshu

@powdrhound here on the forum has info. I can't find the old thread where it was discussed. I'm not saying this is the case w/ the car that you are looking at, but adding to the discussion that it's interesting that this data seems to be problematic on some cars.