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Around here it's hard to get non ethanol gas. E10 has a stoichiometric AFR of 14.08:1
Tough crowd in here. I'm aware E10 is most common fuel. Just need a reference to baseline on and most people baseline stoich on 14.7 non-ethanol.

-Matt
 

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Tough crowd in here. I'm aware E10 is most common fuel. Just need a reference to baseline on and most people baseline stoich on 14.7 non-ethanol.

-Matt
It's hard to appreciate the work that goes into RTL and assembly reverse-engineering without doing it yourself. To most end-users, DynoJet just wrote a GUI for tuning a Honda ECU. What they don't realize is that all those bytes of Honda data aren't labeled, and DynoJet is painstakingly guessing and checking each and every 2D/3D table and data-point they choose to allow the end-user to access within the software (Power Core + C3).

0.605 V is the stock voltage setting (1.0 lambda); 0.684 V provides a slightly more stable 1.0 lambda target (which is why DJ base maps usually use this value).

This could be a byproduct of E10 fuel, or (more likely) the fact that Honda used a single-wire O2 sensor which has no provisions for self-heating, and therefore is horribly inaccurate until your engine is smoking hot. If you commute less than 20-30 minutes and live anywhere other than 75+ degree weather, your OEM narrowband is working only a little better than nothing at all (i.e. a well-tuned open loop map).

It would behoove all would-be tuners to learn to refer to AFR by lambda numbers rather than AFR. Lambda is blind to fuel type.

I referred everyone to a book earlier in the thread which is a good resource to all those interested in tuning. Another good book is 'How to Tune and Modify Motorcycle Engine Management Systems' by Tracy Martin. This book is less usable from a technical perspective, but gives good insight into the world of motorcycle EFI and why it lags behind 4-wheeled platforms. DynoJet's history is featured quite prominently in this book. aRacer is not, however any discussion of standalone management would apply.
 

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Tough crowd in here.
This is very civil compared to a few threads here


Honestly Matt really do appreciate yours Dans and Mr.Saturns efforts,,, Be patient with us were a bunch of End Users not tuners lol

Its not too far off from the old 4 tire Honda and Acura forums I used to frequent back in the day.

I've got mrsaturn (mrlambda?) who wants me to keep it by the book and dubsolo who wants me to break it down barney style.

I'll be over here in the corner doing my thing keeping it balanced and professional 🙂. Keep the questions coming!

-Matt
 

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Steve,

I revisited the database with some fresh eyes. Looks like there is a strong possibility "Component Protect" is actually "Decel Fuel Cut-Off" and vice-versa.

If you don't mind confirming "Master Switch, Component Protect" works to disable DFCO I'll get the section and parameters renamed and into an update. Otherwise, I'll try to get someone in our team to verify on our house Grom.


-Matt

P.S. Pending verification, it looks like the 17-19 has facilities for DFCO to come on soft and lead into a hard cut although the soft cut is not configured from the factory. DFCO is enabled by default in the 17-19. The 14-15 only has facilities for a full cut DFCO and is disabled by default.

P.S.S. Also pending verification, the current "Decel Fuel Cut-Off" parameters look to control a fuel cut-off that only comes in at very low throttle. Possibly to protect for a vacuum leak or other mechanical failure.
You seemed very confused by some things and you are a freaking engineer at DynoJet. So do you now see how the owners of your devices are confused? I know the extremely poor documentation and general not knowing WTF is going on at DynoJet isn't your fault, but this is both laughable and extremely frustrating as a customer. DynoJet should be embarrassed.

I appreciate you trying to help us work through the issues even if you're not the expert. Thank you.
 

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Steve,

I revisited the database with some fresh eyes. Looks like there is a strong possibility "Component Protect" is actually "Decel Fuel Cut-Off" and vice-versa.

If you don't mind confirming "Master Switch, Component Protect" works to disable DFCO I'll get the section and parameters renamed and into an update. Otherwise, I'll try to get someone in our team to verify on our house Grom.


-Matt

P.S. Pending verification, it looks like the 17-19 has facilities for DFCO to come on soft and lead into a hard cut although the soft cut is not configured from the factory. DFCO is enabled by default in the 17-19. The 14-15 only has facilities for a full cut DFCO and is disabled by default.

P.S.S. Also pending verification, the current "Decel Fuel Cut-Off" parameters look to control a fuel cut-off that only comes in at very low throttle. Possibly to protect for a vacuum leak or other mechanical failure.
You seemed very confused by some things and you are a freaking engineer at DynoJet. So do you now see how the owners of your devices are confused? I know the extremely poor documentation and general not knowing WTF is going on at DynoJet isn't your fault, but this is both laughable and extremely frustrating as a customer. DynoJet should be embarrassed.

I appreciate you trying to help us work through the issues even if you're not the expert. Thank you.
I'm not confused by anything. I'm investigating and fixing a reported problem and asking someone (thats not you) to run a test. I could come with the b.s. and try to sugar coat it and talk around it, but an honest man admits when he makes a mistake.

You're really going to knock me and blatantly disrespect me for being honest?

50-50... Can't win if you do, can't win if you don't.

-Matt
 

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I'm not confused by anything. I'm investigating and fixing a reported problem and asking someone (thats not you) to run a test. I could come with the b.s. and try to sugar coat it and talk around it, but an honest man admits when he makes a mistake. You're really going to knock me for that?

50-50... Can't win if you do, can't win if you dont.

-Matt
Statements like "Looks like there is a strong possibility" and "pending verification" lead me to believe you were confused on some things.

I wasn't knocking you at all. I even stated that I know this isn't your fault and I also thanked you. Sorry for the misunderstanding, but I didn't direct anything towards you personally.
 

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Statements like "Looks like there is a strong possibility" and "pending verification" lead me to believe you were confused on some things.

I wasn't knocking you at all. I even stated that I know this isn't your fault and I also thanked you. Sorry for the misunderstanding, but I didn't direct anything towards you personally.
When you take statements out of context you can twist the narrative to sound however you want it to. I accept the apology, thank you.

Outside of the pre-load tunes and C3 software, Honda is my project through and through. I don't mind coming out of my normal wheelhouse to help you guys out. I'm here on my own accord.

Is there anything I can help you with?

-Matt
 

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Another question...
Should we push the smooth button after a tunescript correction in tunelab or leave it straight like tunelab corrected it?


Enviat des del meu LG-H870 usant Tapatalk
 

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Another question...
Should we push the smooth button after a tunescript correction in tunelab or leave it straight like tunelab corrected it?


Enviat des del meu LG-H870 usant Tapatalk
Post a screen shot of the table and highlight the corrected area. The best I can offer you is a suggestion.

-Matt
 

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I don't have a problem breaking it down for you. Unfortunately, there are just not enough hours in a day to do that AND give you the cool stuff you (and other Honda) guys are asking for. Check this link out, explains everything you should need to know: https://www.aa1car.com/library/o2sensor.htm.
0.605 V is the stock voltage setting (1.0 lambda); 0.684 V provides a slightly more stable 1.0 lambda target (which is why DJ base maps usually use this value).
THANK YOU! Between the two of these post I've grasped what I was after... Sheeesh
 

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Post a screen shot of the table and highlight the corrected area. The best I can offer you is a suggestion.

-Matt
This saturday ill spend the day at work working on the bike at the dyno. I will post you the results afterwards.

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When you take statements out of context you can twist the narrative to sound however you want it to. I accept the apology, thank you.

Outside of the pre-load tunes and C3 software, Honda is my project through and through. I don't mind coming out of my normal wheelhouse to help you guys out. I'm here on my own accord.

Is there anything I can help you with?

-Matt
I only took those statements out of context only to highlight them. When I read them they were in context. But, as we know, text can be interpreted in a way it wasn't intended and I think that is what I did in this case. I really appreciate you being here especially on your own time. I'm sure others would agree.

I just have questions at this point.

1. What's the best way to learn this software?
2. What would you suggest I read/study/etc to learn the basics of tuning FI like on the Grom?
3. What would be a good starting setting for switching from CL to OL. That's one step that's necessary before following the instructions for taking the PV3+WBCX logs and using them to update the map.

Thank you.
 

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I only took those statements out of context only to highlight them. When I read them they were in context. But, as we know, text can be interpreted in a way it wasn't intended and I think that is what I did in this case. I really appreciate you being here especially on your own time. I'm sure others would agree.

I just have questions at this point.

1. What's the best way to learn this software?
2. What would you suggest I read/study/etc to learn the basics of tuning FI like on the Grom?
3. What would be a good starting setting for switching from CL to OL. That's one step that's necessary before following the instructions for taking the PV3+WBCX logs and using them to update the map.

Thank you.
Here are my opinions:

1a. Read the descriptions under each table and parameter. I wrote all of these and these are about as much "help" as I can really give you with the strategy. If something needs further explanation, feel free to ask me specifics and I can even get those descriptions updated. I already have some ideas for improvement from this thread.
1b. Trial and error. As long as your changes aren't crazy and you aren't running forced induction or nitrous, you'd have to have a really bad tune in there to blow your motor.
1c. Ask questions. Join a Facebook user's group. I am a member of "Guild of EFI Tuners" and "Dyno Tuning and Engine Management". I see questions there from newbs to guys that have been tuning for 30+ years. There is nothing particularly unique about C3 software or the Honda strategy that an intermediate tuner would find out of sorts.
1d. The Grom's ECU uses a strategy close to the 90's OBD1 Civic strategy (fuel pulsewidth tables, cable throttle, various compensations). You might find guides and users manuals out there for other Honda platforms that are worth a read. Parameters are always going to be named differently but all do the same thing. For instance, injector latency can also be called deadtime, battery offset or opening delay.
1e. There is a bit more leg work to do because the ECU is not set up with an easy-peasy VE table or a MAF sensor you can re-scale.

2. Unfortunately there isn't anything specific that I am aware of. From my personal experience, this is one of the most straightforward and easiest to tune platforms once you understand the strategy (not tuning VE or MAF rescaling). Look up how to tune a Ford Coyote (Mustang 5.0) ignition system and you'll understand what I mean!

3. I'll let someone else answer that for you.

-Matt
 

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Here are my opinions:

1a. Read the descriptions under each table and parameter. I wrote all of these and these are about as much "help" as I can really give you with the strategy. If something needs further explanation, feel free to ask me specifics and I can even get those descriptions updated. I already have some ideas for improvement from this thread.
1b. Trial and error. As long as your changes aren't crazy and you aren't running forced induction or nitrous, you'd have to have a really bad tune in there to blow your motor.
1c. Ask questions. Join a Facebook user's group. I am a member of "Guild of EFI Tuners" and "Dyno Tuning and Engine Management". I see questions there from newbs to guys that have been tuning for 30+ years. There is nothing particularly unique about C3 software or the Honda strategy that an intermediate tuner would find out of sorts.
1d. The Grom's ECU uses a strategy close to the 90's OBD1 Civic strategy (fuel pulsewidth tables, cable throttle, various compensations). You might find guides and users manuals out there for other Honda platforms that are worth a read. Parameters are always going to be named differently but all do the same thing. For instance, injector latency can also be called deadtime, battery offset or opening delay.
1e. There is a bit more leg work to do because the ECU is not set up with an easy-peasy VE table or a MAF sensor you can re-scale.

2. Unfortunately there isn't anything specific that I am aware of. From my personal experience, this is one of the most straightforward and easiest to tune platforms once you understand the strategy (not tuning VE or MAF rescaling). Look up how to tune a Ford Coyote (Mustang 5.0) ignition system and you'll understand what I mean!

3. I'll let someone else answer that for you.

-Matt
Damn... I was waiting your answer for question 3...
I set mine feedback fuel hysteresis on at 5000 and off at 4800...
Havent done any change in feedback fuel maximum tps table yet (mine is a 2014 euro model)... But might try this weekend some changes in that last section (maybe maximum tps table set at half throttle...
Not saying at all is an answer to your question, just saying whats my set up....

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I've got mrsaturn (mrlambda?) who wants me to keep it by the book and dubsolo who wants me to break it down barney style.
The lambda comment wasn't directed at you - I already know you know the difference between lambda and AFR for a specific fuel. Someone else split hairs with E10 and my point was that if they were thinking in terms of lambda, it wouldn't matter and they wouldn't have had to ask the question to begin with.

You seemed very confused by some things and you are a freaking engineer at DynoJet. So do you now see how the owners of your devices are confused? I know the extremely poor documentation and general not knowing WTF is going on at DynoJet isn't your fault, but this is both laughable and extremely frustrating as a customer. DynoJet should be embarrassed.
A single incorrect value in hex mapping a table would cause this error I was discussing with Matt. 50-50, you should spend time on the RomRaider forums to appreciate the work being done here. Dump a fresh ROM, map it, and come back. See you in a year or two. Clearly being sarcastic here, but doing this kind of reverse engineering is very difficult and prone to mistakes along the way. Something may look like an ignition advance compensation table and have nothing to do with ignition at all.

I just have questions at this point.

1. What's the best way to learn this software?
Screwing around with it in your free time.

I concur that a few things are more difficult in this platform than VE, speed density, MAF, etc. - the biggest being a change in throttle requiring a major remap.

2. What would you suggest I read/study/etc to learn the basics of tuning FI like on the Grom?
The two books I posted.

3. What would be a good starting setting for switching from CL to OL. That's one step that's necessary before following the instructions for taking the PV3+WBCX logs and using them to update the map.
This is entirely up to you, as the tuner to decide, but I'll throw you a bone - what is your usual cruise RPM? Do you care about fuel economy? If so, the switch point should be about 500-800 above cruise and utilize hysteresis to prevent jitter.
 

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Would you mess with injector latency if you're switching from a stock injector to a PCX150? Or is that more if you're switching to a totally different brand of aftermarket injector?
 

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Dumping the ROM from a bike equipped with a PCX150 is a good solution to this problem. That's one nice thing about OEM injectors - someone else did the homework for you.

The other reason latency isn't important on this bike is we have a fixed pressure fuel system rather than a vacuum controlled 1:1 rising rate regulator. That turns the latency table from a 3D affair to a 2D table that only references system voltage. Even then, latency tables usually use absurd voltage ranges at the high and low end that you never see in reality.

From a tuning standpoint, if you have the latency wrong, you've just modeled your injector wrong and tuning the fuel map will *usually* compensate since the voltage output of the bike is repeatable in most situations.

The real data I like to see is small IPW (non-linear) flow data. This is the kind of info that allows you to idle a 125 cc bike on a 400 cc injector if you really wanted to (and the ECU allowed for this compensation). Exaggerating a bit, but given Matt's background with 90's Honda tuning, I'm sure he remembers the days when this type of data wasn't available so you had to settle for a lumpy idle when you had 4 x 1000 cc injectors on a sub-2.0 liter 4 banger.
 

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Here are my opinions:

1a. Read the descriptions under each table and parameter. I wrote all of these and these are about as much "help" as I can really give you with the strategy. If something needs further explanation, feel free to ask me specifics and I can even get those descriptions updated. I already have some ideas for improvement from this thread.
1b. Trial and error. As long as your changes aren't crazy and you aren't running forced induction or nitrous, you'd have to have a really bad tune in there to blow your motor.
1c. Ask questions. Join a Facebook user's group. I am a member of "Guild of EFI Tuners" and "Dyno Tuning and Engine Management". I see questions there from newbs to guys that have been tuning for 30+ years. There is nothing particularly unique about C3 software or the Honda strategy that an intermediate tuner would find out of sorts.
1d. The Grom's ECU uses a strategy close to the 90's OBD1 Civic strategy (fuel pulsewidth tables, cable throttle, various compensations). You might find guides and users manuals out there for other Honda platforms that are worth a read. Parameters are always going to be named differently but all do the same thing. For instance, injector latency can also be called deadtime, battery offset or opening delay.
1e. There is a bit more leg work to do because the ECU is not set up with an easy-peasy VE table or a MAF sensor you can re-scale.

2. Unfortunately there isn't anything specific that I am aware of. From my personal experience, this is one of the most straightforward and easiest to tune platforms once you understand the strategy (not tuning VE or MAF rescaling). Look up how to tune a Ford Coyote (Mustang 5.0) ignition system and you'll understand what I mean!

3. I'll let someone else answer that for you.

-Matt
I need to learn the basics. That's where I'm starting. I just don't want to start by reading information that doesn't apply or is outdated. Lots of good info that you provided. Thank you.


A single incorrect value in hex mapping a table would cause this error I was discussing with Matt. 50-50, you should spend time on the RomRaider forums to appreciate the work being done here. Dump a fresh ROM, map it, and come back. See you in a year or two. Clearly being sarcastic here, but doing this kind of reverse engineering is very difficult and prone to mistakes along the way. Something may look like an ignition advance compensation table and have nothing to do with ignition at all.

Screwing around with it in your free time.

I concur that a few things are more difficult in this platform than VE, speed density, MAF, etc. - the biggest being a change in throttle requiring a major remap.

The two books I posted.

This is entirely up to you, as the tuner to decide, but I'll throw you a bone - what is your usual cruise RPM? Do you care about fuel economy? If so, the switch point should be about 500-800 above cruise and utilize hysteresis to prevent jitter.
I understand the magnitude of the work that was put in just to make the PV3 work. It's liken to people jailbreaking the iPhone or gaining root access to an Android phone, but way more complicated. I never insinuated this was easy. But when a company releases a product to market it should be ready to go in terms of documentation and support. In this case it seems they rushed it to market and are backtracking to catch up the documentation (maybe?) and support.

I searched the thread to find the two books you recommended. They are:

'How to Tune and Modify Automotive Engine Management Systems' by Jeff Hartman
'How to Tune and Modify Motorcycle Engine Management Systems' by Tracy Martin

Very interesting that the titles are so similar yet from two different people. I will check them out. Thank you.

I don't care about fuel economy. I want the best performance without risking being too lean.
 
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