Ignition rev 6 and Kaboom?
#16
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I'd take the 2nd one... it looks like it was driven enthusiastically but no hard money shifts (except some range 4's but that happened quite a long time ago). The 1st one was just recently money shifted all the way up in range 6. To even consider a car with range 6's (no matter how it's recorded since no one actually knows the inner programming of the DME), you'd need to have way more operating hours on it before it's considered safe, and even then you might want to do a compression and leakdown test.
#17
Race Director
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I'd take the 2nd one... it looks like it was driven enthusiastically but no hard money shifts (except some range 4's but that happened quite a long time ago). The 1st one was just recently money shifted all the way up in range 6. To even consider a car with range 6's (no matter how it's recorded since no one actually knows the inner programming of the DME), you'd need to have way more operating hours on it before it's considered safe, and even then you might want to do a compression and leakdown test.
These single digit "overrevs" are computer errors, nothing more.
#18
Race Director
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I am not so sure about this....... It counts "ignitions" and not revolutions in some band .... what if you let the clutch out but don't apply gas... and shoot the RPMs up into band 6? Most computers are smart to cut gas for mileage if nothing else. When you car coasts down a hill, you are in gear and you let off the gas and coast, the computer cuts gas..... so no ignitions????
I have tracked live values from my Durametric and the car accuratly tracks RPM, digitally. Why doesn't the computer track RPMs in these higher bands and only "ignitions"? If the engine is spinning in an upper range in a danger zone, why doesn't it just track RPMs and time? The data is certainly there.
This may be more complex than we think... the computer may be exactly correct and functioning properly. The problem may be in our understanding.
Peace
Bruce in Philly
I have tracked live values from my Durametric and the car accuratly tracks RPM, digitally. Why doesn't the computer track RPMs in these higher bands and only "ignitions"? If the engine is spinning in an upper range in a danger zone, why doesn't it just track RPMs and time? The data is certainly there.
This may be more complex than we think... the computer may be exactly correct and functioning properly. The problem may be in our understanding.
Peace
Bruce in Philly
The system is fine
#19
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No, this car was not money shifted to range 6. use your head. you can't have the same number number of ignitions in a single event in 2 categories. the lower category will always have a higher ignition count.
These single digit "overrevs" are computer errors, nothing more.
These single digit "overrevs" are computer errors, nothing more.
#21
Race Director
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If you know for certain how it records overrevs, then they must be errors. If someone were accelerating and went down a gear at redline intending to go up a gear, yet only let out the clutch slightly but then clutched in asap, would it not be possible to record range 5-6 but not ranges 1-4 for example? I'm curious to know exactly how the DME records ignitions there.
#22
RL Community Team
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No, this car was not money shifted to range 6. use your head. you can't have the same number number of ignitions in a single event in 2 categories. the lower category will always have a higher ignition count.
These single digit "overrevs" are computer errors, nothing more.
These single digit "overrevs" are computer errors, nothing more.
You could just count, like ignitions, the number of revolutions in a band. What is odd about the ignitions, is that you get three ignitions for every revolution, assuming you get spark every cycle.... I do know that cars in general "cut gas" when off the throttle, I am not sure about firing a plug when there is nothing to burn. Are the engineers more concerned about applying gas in those ranges or just the engine spinning up not under load?
I am skeptical of flukes or anomalies in these systems as engineers worked pretty hard to get anti-knock and other control systems down pat. I am just skeptical that because it may not make sense to us, that we can then conclude the data was bad.
Peace
Bruce in Philly
#23
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Could be a missed shift.
Could be a glitch.
Could be a tune.
Could be a sign the DMW was laundered.
A DME Report is just one tool, of many, used to do your due diligence in the buying process.
You could always purchase a powertrain warranty as a hedge.
Could be a glitch.
Could be a tune.
Could be a sign the DMW was laundered.
A DME Report is just one tool, of many, used to do your due diligence in the buying process.
You could always purchase a powertrain warranty as a hedge.
#24
Three Wheelin'
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I am just starting to pay more attention to these threads.
Can anyone briefly explain what the different rev counts mean and how this is done?
I have hit my rev limiter a few times, but it then cuts ignition so one simply gets off the gas. How does one go into these high ranges when it should cut the ignition?
Can anyone briefly explain what the different rev counts mean and how this is done?
I have hit my rev limiter a few times, but it then cuts ignition so one simply gets off the gas. How does one go into these high ranges when it should cut the ignition?
On the practical side, why would anyone want to hit the rev-limiter? It seems to me that this is poor driving more than spirited driving. Hit the rev-limiter and your engine just down for a moment. How is this fun. It's like, "lets see how hard I can push my engine and I don't care if it shuts down". Accidents/inattention happens but a better driver, driving spiritedly, might hit the limiter much less frequently. Lots of Range 1 and 2s speak more about how the car was treated than if there is any damage. And if this is axiomatic, then a car with a lot of Range 1 and 2s might have other wear related issues associated with hard (poor) driving that you also ought to consider.
You can buy a car with lots of over-revs (X) or one with many fewer (X-Y). What you really need to do is ascertain how much more the fewer Range 1/2 is worth to your pocketbook, peace of mind and potential for future repairs.
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#27
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My understanding is that selecting Sport mode (when you have SC option) changes the rev limiter characteristic so that ignition is not cut and you can "ride" the limiter. This could be advantageous for track days or autocross where a shift change would not be practical. I don't have sport chrono so I am only going by what I recall reading on RL.
#28
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My understanding is that selecting Sport mode (when you have SC option) changes the rev limiter characteristic so that ignition is not cut and you can "ride" the limiter. This could be advantageous for track days or autocross where a shift change would not be practical. I don't have sport chrono so I am only going by what I recall reading on RL.
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Originally Posted by scorcherjf
Exactly. There are some places on the track where it would be a waste of time to upshift then have to immediately downshift for the corner. I've hit the limiter and "ridden" it for a second or two and it still did not log any range 1 over revs. I have a durametric and checked before and after each track day and I know for a fact I hit the limiter.
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