What's your SI looking like today?

If you could have one mod right now, what would it be?


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Doc_Mello

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Hondata has a series of data logs showing long term harm that were linked in the threads from this video first posting

https://www.civicx.com/forum/threads/oh-no-not-another-bov-thread.57978/
Lol yes, i've seen those. My natural question when I first saw those was how could they determine long term issues from early/mid 2017 (the dates of the hondata posts)? The first year of this platform was 2017, so released middle to late 2016.

I understand the reasoning completely...just curious how much damage can be caused after true long term usage (maybe 3+ years). The damage they refer could/would happen, is that after say... 2 years? 5 years? 10 years? Could someone put one on knowing they won't have the car for more than 5 years and not see an issue?
That was my thinking also. Yes, I saw those graphs, but I'm not convinced that qualifies as sufficient longitudinal data for this question. I meant, like, 10K+ tuned miles with a BOV, and a 500 mile datalog of LTFTs. Plus, other metrics of 'the car not running right' WRT long-term harm, like plug fouling, or injectors failing prematurely. Again, I may have missed it, but I'm pretty sure no one's done such a thorough investigation.

I think a thorough investigation on such a popular topic is warranted, something beyond 'Hondata showed two graphs of relatively short intervals of STFTs'. For example, here's the original link to those two graphs: http://hondata.com/forum/viewtopic.php?p=92218

X-axis: airflow meter, a metric presumably measured in seconds (as denoted by the /s)
Y-axis: short term fuel trims

- Control condition (no BOV): the average of the metering adjustments (as indicated by the blue line) hovers around 0 (where it should be)
- Experimental condition (w/ BOV): the average of the metering adjustments starts around -5, but returns to 0 in 22 seconds. I want to know the long-term potential for harm from those 22 seconds, not to mention the condition of the test. Was it one dyne pull? Or a regular driving datalog?

And another Q: it's my understanding that negative FTs = less fuel. So, wouldn't that mean that the engine is running lean, not rich, in those seconds of negative STFT? Still no bueno, sure, but a different story.

Again, I'd like to see more parameters, and more data. ...because I'm a data scientist. ?
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rhino

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That was my thinking also. Yes, I saw those graphs, but I'm not convinced that qualifies as sufficient longitudinal data for this question. I meant, like, 10K+ tuned miles with a BOV, and a 500 mile datalog of LTFTs. Plus, other metrics of 'the car not running right' WRT long-term harm, like plug fouling, or injectors failing prematurely. Again, I may have missed it, but I'm pretty sure no one's done such a thorough investigation.

I think a thorough investigation on such a popular topic is warranted, something beyond 'Hondata showed two graphs of relatively short intervals of STFTs'. For example, here's the original link to those two graphs: http://hondata.com/forum/viewtopic.php?p=92218

X-axis: airflow meter, a metric presumably measured in seconds (as denoted by the /s)
Y-axis: short term fuel trims

- Control condition (no BOV): the average of the metering adjustments (as indicated by the blue line) hovers around 0 (where it should be)
- Experimental condition (w/ BOV): the average of the metering adjustments starts around -5, but returns to 0 in 22 seconds. I want to know the long-term potential for harm from those 22 seconds, not to mention the condition of the test. Was it one dyne pull? Or a regular driving datalog?

And another Q: it's my understanding that negative FTs = less fuel. So, wouldn't that mean that the engine is running lean, not rich, in those seconds of negative STFT? Still no bueno, sure, but a different story.

Again, I'd like to see more parameters, and more data. ...because I'm a data scientist. ?
neeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeerd!!!
 

healtoe

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That was my thinking also. Yes, I saw those graphs, but I'm not convinced that qualifies as sufficient longitudinal data for this question. I meant, like, 10K+ tuned miles with a BOV, and a 500 mile datalog of LTFTs. Plus, other metrics of 'the car not running right' WRT long-term harm, like plug fouling, or injectors failing prematurely. Again, I may have missed it, but I'm pretty sure no one's done such a thorough investigation.

I think a thorough investigation on such a popular topic is warranted, something beyond 'Hondata showed two graphs of relatively short intervals of STFTs'. For example, here's the original link to those two graphs: http://hondata.com/forum/viewtopic.php?p=92218

X-axis: airflow meter, a metric presumably measured in seconds (as denoted by the /s)
Y-axis: short term fuel trims

- Control condition (no BOV): the average of the metering adjustments (as indicated by the blue line) hovers around 0 (where it should be)
- Experimental condition (w/ BOV): the average of the metering adjustments starts around -5, but returns to 0 in 22 seconds. I want to know the long-term potential for harm from those 22 seconds, not to mention the condition of the test. Was it one dyne pull? Or a regular driving datalog?

And another Q: it's my understanding that negative FTs = less fuel. So, wouldn't that mean that the engine is running lean, not rich, in those seconds of negative STFT? Still no bueno, sure, but a different story.

Again, I'd like to see more parameters, and more data. ...because I'm a data scientist. ?
Alright mr scientist let’s set this experiment up. What else do we need to measure?
 

86salmon

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Negative fuel trim is cutting fuel (injector bandwidth) because there's too much present, a rich condition
 

rhino

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Alright mr scientist let’s set this experiment up. What else do we need to measure?
hold up! we dont need to measure that!
 


rhino

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Good! I was afraid I’d have to embellish on some of the numbers ?
lmao nah you safe! trust me id be screwed also i have a lifted truck!
 

Doc_Mello

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Negative fuel trim is cutting fuel (injector bandwidth) because there's too much present, a rich condition
Ah, so, it’s a post hoc adjustment.

The computer thought there was going to be a certain amount of air going in, but the O2 showed a much lower volume than expected, and since the amount of fuel was computed based on pre-turbo measurement, the computer gets all Keanu like ‘Whoa! Too much fuel, bruh!’, then cuts injector bandwidth.

Something like that? ?
 

86salmon

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Ah, so, it’s a post hoc adjustment.

The computer thought there was going to be a certain amount of air going in, but the O2 showed a much lower volume than expected, and since the amount of fuel was computed based on pre-turbo measurement, the computer gets all Keanu like ‘Whoa! Too much fuel, bruh!’, then cuts injector bandwidth.

Something like that? ?
Honda Civic 10th gen What's your SI looking like today? Screenshot_20211202-195551
 


Doc_Mello

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Alright mr scientist let’s set this experiment up. What else do we need to measure?
First, obligatory...
Honda Civic 10th gen What's your SI looking like today? 1638494449757


Now, a couple of ways to go about this, and the best would be a hyper-controlled experiment, but the most realistic would be a case-control study: any given car running a datalog for, say, 300 miles, then changing the condition by only adding a BOV,
then datalogging another 300 miles. In fact, having multiple cars do this, then assessing the results.

?? Seems simple enough.

I might be tempted if someone buys the BOV for me. ?
 

rhino

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First, obligatory...
1638494449757.png


Now, a couple of ways to go about this, and the best would be a hyper-controlled experiment, but the most realistic would be a case-control study: any given car running a datalog for, say, 300 miles, then changing the condition by only adding a BOV,
then datalogging another 300 miles. In fact, having multiple cars do this, then assessing the results.

?? Seems simple enough.

I might be tempted if someone buys the BOV for me. ?
hey id install one on my car if someone would give me the turbo to put on my car lol
 

bugboy32337

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Alright mr scientist let’s set this experiment up. What else do we need to measure?
Actually ... it's Doctor Scientist ... LOL.
 

joeyp19

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looks great. makes me wish I bought some springs during black friday now lol. These are on the stock suspension?
This photo was taken with the D2 Racing springs installed. I must say though, they have settled a bit and the car looks like its just a tad lower today.
 

healtoe

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First, obligatory...
1638494449757.png


Now, a couple of ways to go about this, and the best would be a hyper-controlled experiment, but the most realistic would be a case-control study: any given car running a datalog for, say, 300 miles, then changing the condition by only adding a BOV,
then datalogging another 300 miles. In fact, having multiple cars do this, then assessing the results.

?? Seems simple enough.

I might be tempted if someone buys the BOV for me. ?
Okay new plugs were done 10k kms ago. Recently put msd coils and oil is at 80%
I’ll run the bov until march. Then I’ll take it off and do logs again. It’s backwards to your approach but I don’t feel like taking it off yet lol
I’ll start the logging when I drive to Montreal next Thursday. Does it have to be one log file or multiple is fine? Since I’ll be stopping for gas and food along the way
 


 


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