Stage 1
08-28-2013, 10:52 PM
#126
08-28-2013, 10:54 PM
#127
Correct .
There are three LTFT areas that seem tied to how many g/s the maf is reading .
this is from memory but is close enough .......
0-8 idle
8-20
20+
I am not convinced your approach is the best one . The way we generally approach tuning these is to pay more attention to LTFT than STFT and to minimise that open loop LTFT before doing any OL tuning.
There are three LTFT areas that seem tied to how many g/s the maf is reading .
this is from memory but is close enough .......
0-8 idle
8-20
20+
I am not convinced your approach is the best one . The way we generally approach tuning these is to pay more attention to LTFT than STFT and to minimise that open loop LTFT before doing any OL tuning.
Don't we want to start with 0's across the board for LTFT's before starting into open loop?
08-28-2013, 10:56 PM
#128
08-29-2013, 12:37 PM
#129
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Hey, no-coast-punk, just wanted to thank you for all your contributions to this thread, which basically gave me enough information to start on my own tune!
I've been loading a new tune and resetting my fuel trims every time I drive to school in the morning (~80*). So far I've been using STFT's to adjust my closed loop VE, and I've been using Actual Lambda/Commanded Lambda to adjust my OL WOT tuning.
I also started with using a flat >1< across the board for the VE, just because I think it's easier to tune from and blends much better than the stock map. After adjusting, I realized that the cruising values are all above 1.00, and the OL WOT values are below 1.00, meaning any positive LTFT value at all with throw the OL WOT fuel trims in the wrong direction, especially if your AFR's are already set too low - or worse - stock
To reiterate my plan:
1. Keep LTFT's at ZERO for tuning
2. Use STFT's (when you're at/near target afr for a steady load) for cruising VE's.
3. Use Actual Lambda/ Commanded lambda as a % for VE adjustment.
Seems to be working out so far, thanks for pointing me in the right direction!
I also started with using a flat >1< across the board for the VE, just because I think it's easier to tune from and blends much better than the stock map. After adjusting, I realized that the cruising values are all above 1.00, and the OL WOT values are below 1.00, meaning any positive LTFT value at all with throw the OL WOT fuel trims in the wrong direction, especially if your AFR's are already set too low - or worse - stock
To reiterate my plan:
1. Keep LTFT's at ZERO for tuning
2. Use STFT's (when you're at/near target afr for a steady load) for cruising VE's.
3. Use Actual Lambda/ Commanded lambda as a % for VE adjustment.
Seems to be working out so far, thanks for pointing me in the right direction!
09-03-2013, 02:43 AM
#130
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Hi guys.
I have question for you about best Target AFR in closed loop for improve fuel economy.
I already did MAF calibration, and my LTFT are very closed to zero, even my STFT are close to zero before VE fine adjustments.
I would like to know what AFR target are you using in closed loop, I mean, the car run usually in 14,7 - 14,6 at cruising 120 km/h (3500 rpm aprox) over 50% of load, so I increased the target for that RPM/Load ratios to 15,4 AFR because I saw in wikipedia that its he best fuel economy point, attached its the stoichiometry graphic for gasoline, and fuel economy is a little bit better now.
What to you think about that ???
I have question for you about best Target AFR in closed loop for improve fuel economy.
I already did MAF calibration, and my LTFT are very closed to zero, even my STFT are close to zero before VE fine adjustments.
I would like to know what AFR target are you using in closed loop, I mean, the car run usually in 14,7 - 14,6 at cruising 120 km/h (3500 rpm aprox) over 50% of load, so I increased the target for that RPM/Load ratios to 15,4 AFR because I saw in wikipedia that its he best fuel economy point, attached its the stoichiometry graphic for gasoline, and fuel economy is a little bit better now.
What to you think about that ???
Last edited by asmpbm; 09-03-2013 at 07:16 AM.
09-03-2013, 05:58 AM
#131
The best way to monitor fuel economy is to watch IDC's at a given RPM. Lower IDC's mean you are getting better economy. This eliminates any sensor errors and focuses purely on economy.
Rotaries have weird lambda requirements. Peak power happens somewhere in the 13:1 range, not 12.6.
Rotaries have weird lambda requirements. Peak power happens somewhere in the 13:1 range, not 12.6.
09-15-2013, 11:55 AM
#134
What is so interesting here?
09-15-2013, 12:46 PM
#135
Bingo.
It simply amazes me how quickly so many people lock on to the latest loudmouth poster as an "expert". Been watching this thread for a week+ rolling my eyes and biding my time for the right moment to say something ...
Correct .
There are three LTFT areas that seem tied to how many g/s the maf is reading .
this is from memory but is close enough .......
0-8 idle
8-20
20+
I am not convinced your approach is the best one . The way we generally approach tuning these is to pay more attention to LTFT than STFT and to minimise that open loop LTFT before doing any OL tuning.
There are three LTFT areas that seem tied to how many g/s the maf is reading .
this is from memory but is close enough .......
0-8 idle
8-20
20+
I am not convinced your approach is the best one . The way we generally approach tuning these is to pay more attention to LTFT than STFT and to minimise that open loop LTFT before doing any OL tuning.
09-16-2013, 12:34 PM
#140
what you still don't understand is, if your stock tune had 20.12 LTFT it means something else is MECHANICALLY WRONG with the car, like your jet air hose is broken.
your compensating a mechanical failure with software.
your compensating a mechanical failure with software.
09-17-2013, 01:34 PM
#141
Yellow looks faster.
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No, I understand that. My AP screen broke and I didnt get to do any logs or what not for a month. I got it back and did the logs again, and there was a change. I was just pointing that out.
09-19-2013, 10:34 AM
#143
Yellow looks faster.
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Just make sure everything on the AP is backed up on the computer. And remember the last map you flashed. It cost me 25$ to have COBB replace it, and then another 10$ to have it shipped back to me. was not THAT bad. took about 2 weeks.
01-14-2014, 04:16 PM
#144
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And he's a loudmouth for helping people? Get a grip, behavior like that is exactly why our car has the most poisonous community I have ever seen for any car. What makes your resume stand out more than his? I'd say working on race cars does qualify him as an expert, if not what does? Post count? sheesh.. Regardless if your going to throw insults, at least back it up with some sort of argument, it isn't a given that you know what you are talking about fyi. So could we actually discuss the theories, instead of throwing insults?
01-14-2014, 04:54 PM
#145
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Team was one of the original beta testers for the development of the Cobb on the RX-8 and is probably one of the best NA RX-8 tuners here.
It doesn't matter what the expert tuners do on other platforms because 90% of them could not tune an RX-8 effectively if their lives depended on it. Which is why there are very few competent RX-8 tuners.
It is no ones job to spoon feed anyone. Do your homework and educate yourself.
It doesn't matter what the expert tuners do on other platforms because 90% of them could not tune an RX-8 effectively if their lives depended on it. Which is why there are very few competent RX-8 tuners.
It is no ones job to spoon feed anyone. Do your homework and educate yourself.
01-14-2014, 05:02 PM
#146
Could you, you know, say something then? Why is maf scaling superior to Adjusting VE tables? These forums are really the only place that preach that gospel. Unless there is a specific reason in regards to 8's, no professional tuners do it this way on any car I know of. I see you call out a lot of comments like yours when the shoe is on the other foot, so... any proof, or can you pick out the part you disagree with? He's laid his argument on the table, and his is in line with pretty much every thing I have ever read about the subject. So why is the 8 so special and unique specifically?
And he's a loudmouth for helping people? Get a grip, behavior like that is exactly why our car has the most poisonous community I have ever seen for any car. What makes your resume stand out more than his? I'd say working on race cars does qualify him as an expert, if not what does? Post count? sheesh.. Regardless if your going to throw insults, at least back it up with some sort of argument, it isn't a given that you know what you are talking about fyi. So could we actually discuss the theories, instead of throwing insults?
And he's a loudmouth for helping people? Get a grip, behavior like that is exactly why our car has the most poisonous community I have ever seen for any car. What makes your resume stand out more than his? I'd say working on race cars does qualify him as an expert, if not what does? Post count? sheesh.. Regardless if your going to throw insults, at least back it up with some sort of argument, it isn't a given that you know what you are talking about fyi. So could we actually discuss the theories, instead of throwing insults?
01-14-2014, 05:27 PM
#147
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Team was one of the original beta testers for the development of the Cobb on the RX-8 and is probably one of the best NA RX-8 tuners here.
It doesn't matter what the expert tuners do on other platforms because 90% of them could not tune an RX-8 effectively if their lives depended on it. Which is why there are very few competent RX-8 tuners.
It is no ones job to spoon feed anyone. Do your homework and educate yourself.
It doesn't matter what the expert tuners do on other platforms because 90% of them could not tune an RX-8 effectively if their lives depended on it. Which is why there are very few competent RX-8 tuners.
It is no ones job to spoon feed anyone. Do your homework and educate yourself.
As far as MAF scaling and VE's go there is no difference between this car or any other as far as I'm aware, if you disagree please explain so we can discuss and learn something. If not, I have no interest in a pissing contest or watching ya'll stroke each others ego and offering zero evidence for your or his assertions.
Guess what happens when you do your homework on this car? Google returns comment threads where the so called experts are rolling their eyes because somebody is trying to help someone. Childish IMO..
01-14-2014, 05:28 PM
#148
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