Typical Number of Range 1 and Range 2 Events?
08-01-2018, 12:48 PM
#1
Rennlist Member
Thread Starter
Typical Number of Range 1 and Range 2 Events?
Got the UMW data logger and was able to pull my Range 1 and Range 2 ignition numbers. What's considered a normal amount for them? What's low end and what's excessive?
08-01-2018, 01:28 PM
#2
Three Wheelin'
I'm sure if you post your #s you'll get lots of feedback. Obviously the lower the better for Type 2s, and we like to see a decent amount of hours passed after the last Type 2.
08-01-2018, 02:22 PM
#3
Rennlist Member
I don't think there's a "typical" number. Range 1's are expected on a car that's been driven, and max out at 2^16 = 65,536. Range 2's are hopefully close to 0 and a long time ago.
08-01-2018, 04:29 PM
#4
Rennlist Member
On 996 gen cars, the over-rev report isn't terribly useful. You'll get range one counts just from driving the car the way it is meant to be driven, and it is possible to accumulate some range two WITHOUT a mechanical over-rev, just by hitting rev limiter on fast accel (sometimes phantom range 2's as well).
A high range two count with a low number of hours between last event and current hours is the only thing that might cause any concern at all imho.
997 expanded to six ranges, so you can really see if there was a mechanical over rev.
A high range two count with a low number of hours between last event and current hours is the only thing that might cause any concern at all imho.
997 expanded to six ranges, so you can really see if there was a mechanical over rev.
08-01-2018, 04:39 PM
#5
RL Community Team
Rennlist Member
Rennlist Member
^ +1
08-01-2018, 04:39 PM
#6
Three Wheelin'
you can hit range 2s in 996 just by running through the gears and shifting fast at redline, or by revving it in neutral. over rev report on these cars is basically useless.
08-02-2018, 12:15 PM
#7
Rennlist Member
On 996 gen cars, the over-rev report isn't terribly useful. You'll get range one counts just from driving the car the way it is meant to be driven, and it is possible to accumulate some range two WITHOUT a mechanical over-rev, just by hitting rev limiter on fast accel (sometimes phantom range 2's as well).
A high range two count with a low number of hours between last event and current hours is the only thing that might cause any concern at all imho.
997 expanded to six ranges, so you can really see if there was a mechanical over rev.
A high range two count with a low number of hours between last event and current hours is the only thing that might cause any concern at all imho.
997 expanded to six ranges, so you can really see if there was a mechanical over rev.
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08-02-2018, 07:34 PM
#8
Track Day
AFAIK the 996 was the first 911 to have over rev counters and yes, the 996 2 ranges are indicative of the way the car was driven but they don't have enough granularity to be terribly useful IMHO.
What I'd like to know is if you have a range 2, can I assume that also triggered a range 1? Not particularly useful and maybe academic but when you get to the 997's with 6 ranges, it potentially does make a difference. Also, since the ECU is just counting ignitions you get 3 counts for every complete turn of the crank at that range level. So, if someone does do the money shift yet escapes catastrophic damage (at least immediately) will you get a flurry of range 2's say if you hit 8k RPM's? I'm assuming the answer is yes but unless the ECU would log the timestamp of each over rev count, it is again academic. Only the most recent over rev ignition has a timestamp.
I also agree that you can get a range 2 just by aggressive driving and not by a mechanical over rev. In talking to a good friend who is a certified Porsche mechanic, accelerating hard in a low gear and shifting at or close to red line, the momentum of the engine will trigger a range 2. He called it a "rev flair".
What I'd like to know is if you have a range 2, can I assume that also triggered a range 1? Not particularly useful and maybe academic but when you get to the 997's with 6 ranges, it potentially does make a difference. Also, since the ECU is just counting ignitions you get 3 counts for every complete turn of the crank at that range level. So, if someone does do the money shift yet escapes catastrophic damage (at least immediately) will you get a flurry of range 2's say if you hit 8k RPM's? I'm assuming the answer is yes but unless the ECU would log the timestamp of each over rev count, it is again academic. Only the most recent over rev ignition has a timestamp.
I also agree that you can get a range 2 just by aggressive driving and not by a mechanical over rev. In talking to a good friend who is a certified Porsche mechanic, accelerating hard in a low gear and shifting at or close to red line, the momentum of the engine will trigger a range 2. He called it a "rev flair".
08-03-2018, 09:20 AM
#9
Rennlist Member
AFAIK the 996 was the first 911 to have over rev counters and yes, the 996 2 ranges are indicative of the way the car was driven but they don't have enough granularity to be terribly useful IMHO.
What I'd like to know is if you have a range 2, can I assume that also triggered a range 1? Not particularly useful and maybe academic but when you get to the 997's with 6 ranges, it potentially does make a difference. Also, since the ECU is just counting ignitions you get 3 counts for every complete turn of the crank at that range level. So, if someone does do the money shift yet escapes catastrophic damage (at least immediately) will you get a flurry of range 2's say if you hit 8k RPM's? I'm assuming the answer is yes but unless the ECU would log the timestamp of each over rev count, it is again academic. Only the most recent over rev ignition has a timestamp.
I also agree that you can get a range 2 just by aggressive driving and not by a mechanical over rev. In talking to a good friend who is a certified Porsche mechanic, accelerating hard in a low gear and shifting at or close to red line, the momentum of the engine will trigger a range 2. He called it a "rev flair".
What I'd like to know is if you have a range 2, can I assume that also triggered a range 1? Not particularly useful and maybe academic but when you get to the 997's with 6 ranges, it potentially does make a difference. Also, since the ECU is just counting ignitions you get 3 counts for every complete turn of the crank at that range level. So, if someone does do the money shift yet escapes catastrophic damage (at least immediately) will you get a flurry of range 2's say if you hit 8k RPM's? I'm assuming the answer is yes but unless the ECU would log the timestamp of each over rev count, it is again academic. Only the most recent over rev ignition has a timestamp.
I also agree that you can get a range 2 just by aggressive driving and not by a mechanical over rev. In talking to a good friend who is a certified Porsche mechanic, accelerating hard in a low gear and shifting at or close to red line, the momentum of the engine will trigger a range 2. He called it a "rev flair".
08-03-2018, 11:43 AM
#10
Rennlist Member
Despite the fact that the general consensus among knowledgeable people is that the DME report isn't terribly useful on a 996TT, you will still get buyers all "revved up" over a DME report supplied with a PPI. Although I don't consider myself an expert, as I understand it, this is especially if the car has a tune to raise the redline. Someone with more knowledge than I can speak to the issue of the effect of a tune on a DME over-rev report.
08-03-2018, 01:27 PM
#11
Rennlist Member
I'm thinking it's the money shifts everyone wants to detect, not bumping off red line during hard acceleration. Correct me if I'm wrong, but don't our cars have the same rev limiters installed that the older ones had? My understanding is the rev limiter can't protect from a money shift but can act in time to protect from what you call rev flair. That doesn't mean it woudn't still register on the counter as a range 2.
A lot of folks out there seem to have the (incorrect) assumption that all Range 2's indicate a mechanical overrev. I'm glad we're correcting the myth around here.
08-03-2018, 08:07 PM
#12
Rennlist Member
And for every individual person here that gets the correct picture, 100 new folks get the incorrect story over on BAT...
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brontosaurus (02-25-2021)
08-04-2018, 04:32 PM
#14
Overrevs on 996s are relatively meaningless besides indicating you probably have a raised redline. I installed a brand new ECU four years ago with 0/0 across the board and within 10k miles have maxed out both range 1s and 2s at 65k+ each with no mechanical overrevs. If you miss a shift and zing it high enough to damage it, you’ll know it...
08-06-2018, 10:20 AM
#15
If a 996 turbo is running a Cobb tuner say in valet mode does anyone know if I go over 4 k rpm which is the limit set by program would that show as over rev on ECU. Or would it be cleared when going back to factory tune. I leave it on valet teaching my son to drive manual to keep over revs if by accident down while he is learning.