Excited and worried at the same time!!
- Thread starter snoon
- Start date
i hear what your saying, 11.5 to 12 fine, although I would stick to 11-11.5 (cause I like safety/dont know how to tune
) Ive been looking at the Nisan std maps, I Wonder why Nissan with their turbo cars went for 10 AFR on full load?
11.5 AFR is a little too rich. You will smell unburnt petrol at that level and it will start to lose power. Even after a lot of fine tuning you can find the AFR's jump around by 0.2 or so on the road so you do need a margin of error but 11 to 11.5 is not a sensible starting point.
Also what is full boost? I mapped a friends car to 510hp where full boost is 2.2Bar (Peak at 2.4Bar) His car runs happily at 12-12.2 AFR at peak hp. At the boost levels we are talking about here then a 12.3 to 12.5 AFR would be fine.
That's why I said 12 -12.5 AFR at peak HP is a sensible target range.
I expect the Nissan 10 AFR is a setting you are looking at rather than an actual measurement. Many ECU's try to relate the fuel injector settings to a target AFR but it only adds confusion and should be ignored. All the values I am talking about are measured values. A car running on petrol would be producing so much black smoke at 10 AFR you would notice if Nissan engineers had really mapped their cars to that range.
To be absolutely clear. Do not use any of the advice I have given here as new "settings" in your ECU. It is for you to understand the readings on your lambda sensor.
Jim
Also what is full boost? I mapped a friends car to 510hp where full boost is 2.2Bar (Peak at 2.4Bar) His car runs happily at 12-12.2 AFR at peak hp. At the boost levels we are talking about here then a 12.3 to 12.5 AFR would be fine.
That's why I said 12 -12.5 AFR at peak HP is a sensible target range.
I expect the Nissan 10 AFR is a setting you are looking at rather than an actual measurement. Many ECU's try to relate the fuel injector settings to a target AFR but it only adds confusion and should be ignored. All the values I am talking about are measured values. A car running on petrol would be producing so much black smoke at 10 AFR you would notice if Nissan engineers had really mapped their cars to that range.
To be absolutely clear. Do not use any of the advice I have given here as new "settings" in your ECU. It is for you to understand the readings on your lambda sensor.
Jim
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mine used to run at 10 on full boost, didnt notice any black smoke though, then again its difficult to look when your driving!
Its just I was reading on Nistune website (IIRC) that Nissan always overfuel there cars down to the 10`s, so first job is to take much fuel out of the top end map??
Its just I was reading on Nistune website (IIRC) that Nissan always overfuel there cars down to the 10`s, so first job is to take much fuel out of the top end map??
Has anyone had a wideband on a std car to check what the fueling is on the nissan ecu? Ive just pulled the map off my emanage and its adding very little duty above the standard map at the top end, 4.5% extra. Im seeing 10.8a/f on full boost of just under 1.4 bar on a 3071 and 660 injectors, so id say that the standard map on a standard car would def fuel into the 10's.
Here is the standard fuel map Target AFR, dont know how close to target actual ARF`s get, but you can see they are set to nearly 10 at full load (am I looking at this wrong..)
9 13 16 19 22 26 30 34 38 42 48 54 60 66 76 86
6800 12.89 12.89 12.54 12.22 11.98 11.33 11.20 11.07 10.88 10.63 10.51 10.23 10.06 10.06 10.06 10.06
6400 13.84 13.84 13.63 13.44 12.89 12.14 12.06 11.76 11.40 11.13 10.88 10.57 10.34 10.17 10.17 10.17
6000 14.04 14.04 13.94 13.73 13.07 12.71 12.22 11.76 11.61 11.40 11.13 10.75 10.51 10.40 10.23 10.23
5600 14.25 14.25 14.25 14.04 13.63 13.16 12.80 12.46 12.14 11.76 11.33 10.88 10.69 10.51 10.40 10.40
5200 14.47 14.47 14.47 14.47 14.36 14.04 13.73 13.44 12.89 12.38 11.91 11.27 10.88 10.69 10.40 10.40
4800 14.47 14.47 14.36 14.36 14.36 14.36 14.36 14.36 13.94 12.89 12.06 11.33 10.94 10.81 10.57 10.57
4400 14.47 14.47 14.47 14.36 14.36 14.36 14.36 14.36 14.36 13.84 12.54 11.91 11.40 11.00 10.63 10.63
4000 14.47 14.47 14.47 14.47 14.36 14.36 14.36 14.36 14.36 14.47 12.71 11.91 11.47 11.00 10.69 10.69
3600 14.47 14.47 14.47 14.47 14.36 14.36 14.15 14.15 14.25 14.25 13.44 12.06 11.69 11.07 11.07 11.07
3200 14.47 14.47 14.47 14.47 14.36 14.36 14.36 14.59 14.59 14.59 13.73 12.38 11.91 11.54 11.54 11.54
2800 14.47 14.59 14.59 14.59 14.47 14.47 14.47 14.59 14.59 14.59 13.63 13.07 12.54 12.54 12.54 12.38
2400 14.59 14.47 14.36 14.47 14.47 14.47 14.47 14.47 14.47 14.59 13.25 12.89 12.89 12.89 12.71 12.71
2000 14.36 14.47 14.36 14.25 14.36 14.47 14.47 14.47 14.47 13.84 13.63 13.63 13.63 13.44 13.44 13.44
1600 14.36 14.47 14.36 14.36 14.25 14.36 14.47 14.47 14.47 14.04 13.84 13.84 13.84 13.63 13.63 13.63
1200 14.36 14.36 14.15 14.25 14.25 14.36 14.47 14.47 14.47 14.04 13.63 13.63 13.63 13.63 13.63 13.63
800 14.15 13.94 13.94 13.94 13.94 14.04 14.15 14.15 13.84 13.84 13.84 13.84 13.63 13.63 13.63 13.63
9 13 16 19 22 26 30 34 38 42 48 54 60 66 76 86
6800 12.89 12.89 12.54 12.22 11.98 11.33 11.20 11.07 10.88 10.63 10.51 10.23 10.06 10.06 10.06 10.06
6400 13.84 13.84 13.63 13.44 12.89 12.14 12.06 11.76 11.40 11.13 10.88 10.57 10.34 10.17 10.17 10.17
6000 14.04 14.04 13.94 13.73 13.07 12.71 12.22 11.76 11.61 11.40 11.13 10.75 10.51 10.40 10.23 10.23
5600 14.25 14.25 14.25 14.04 13.63 13.16 12.80 12.46 12.14 11.76 11.33 10.88 10.69 10.51 10.40 10.40
5200 14.47 14.47 14.47 14.47 14.36 14.04 13.73 13.44 12.89 12.38 11.91 11.27 10.88 10.69 10.40 10.40
4800 14.47 14.47 14.36 14.36 14.36 14.36 14.36 14.36 13.94 12.89 12.06 11.33 10.94 10.81 10.57 10.57
4400 14.47 14.47 14.47 14.36 14.36 14.36 14.36 14.36 14.36 13.84 12.54 11.91 11.40 11.00 10.63 10.63
4000 14.47 14.47 14.47 14.47 14.36 14.36 14.36 14.36 14.36 14.47 12.71 11.91 11.47 11.00 10.69 10.69
3600 14.47 14.47 14.47 14.47 14.36 14.36 14.15 14.15 14.25 14.25 13.44 12.06 11.69 11.07 11.07 11.07
3200 14.47 14.47 14.47 14.47 14.36 14.36 14.36 14.59 14.59 14.59 13.73 12.38 11.91 11.54 11.54 11.54
2800 14.47 14.59 14.59 14.59 14.47 14.47 14.47 14.59 14.59 14.59 13.63 13.07 12.54 12.54 12.54 12.38
2400 14.59 14.47 14.36 14.47 14.47 14.47 14.47 14.47 14.47 14.59 13.25 12.89 12.89 12.89 12.71 12.71
2000 14.36 14.47 14.36 14.25 14.36 14.47 14.47 14.47 14.47 13.84 13.63 13.63 13.63 13.44 13.44 13.44
1600 14.36 14.47 14.36 14.36 14.25 14.36 14.47 14.47 14.47 14.04 13.84 13.84 13.84 13.63 13.63 13.63
1200 14.36 14.36 14.15 14.25 14.25 14.36 14.47 14.47 14.47 14.04 13.63 13.63 13.63 13.63 13.63 13.63
800 14.15 13.94 13.94 13.94 13.94 14.04 14.15 14.15 13.84 13.84 13.84 13.84 13.63 13.63 13.63 13.63
Good guide on target AFR's:
http://www.max-boost.co.uk/max-boost/internet_articles/Air fuel metering.htm
As I already said, you are looking at settings not actuals.
http://www.max-boost.co.uk/max-boost/internet_articles/Air fuel metering.htm
As I already said, you are looking at settings not actuals.
Is that based on a N/A or turbo car jim? Couldnt see it specify anywhere.
Best ratio is going to depend on individual set ups and amount of ignition being run and only way of confirming actual best would be comparable runs on a dyno with the same car at different ratios.
It doesn't specify turbo or NA, its more to give a flavour for the different areas of a map and why you might target a different AFR at different fuel settings. Turbo's affect timing more significantly than fueling. It is the interaction between timing and fueling that often causes confusion.
Below is a graphical way to look at AFR's:
On a turbo car you go to 12 to 12.5 but you are still in that peak HP hump area. Ultimately, a car fuel management system is very simple as you have 4 cylinders with different CR's and only one MAF, one lambda and generally common timing. This is before you add in a constantly changing environment and differences in fuel injectors. People like to argue over it but it is a rough science.
If your car is 10.8 at peak HP (between 6K and 6.8K?) then it is about 10% too rich. Even in the greyness of tuning you would find very few people arguing for that AFR when using decent petrol.
Before you start taking out fuel, when your MOT comes round and if you know the people, check your installed sensor against the testers. Handy way to get yours checked once a year ;-) Good engineers rule of thumb is before changing a system, always double check your instruments readings first. (Measure twice, cut once as the carpenter says)
Cheers,
Jim
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The ECU was created by a software engineer at Nissan who probably copied the software from another car before handing it to the engine department who defined the map on a dyno.
The actual is from a calibrated instrument.
As the end user you were never really meant to see the ECU values.
It doesn't really work like that I'm afraid Chris. By moving from 440cc to 660cc injectors you are already adding an extra 30% fuel everytime the injector fires. At 1.4 Bar on a 3071 you would be out of range of the standard map so you have probably changed the standard MAF? This means the amount of fuel your ECU thinks it should be using bears little resemblance to the standard map.
This answer links back to Steve's question on why the target and actual value are often different.
Interesting stuff Jim.
The way i understood the emanage worked as a piggyback system is that it automatically trims the entire fuel map to compensate for the larger injectors, theres a specific data entry for the origional and new injector sizes. ALso MAF changed for a Z32 again this is changed in the emanage menu, not sure if it then converts the signel so as to basically read again pretty much the standard map with no alterations made on the settings.
However, when i looked on the injector map to see what fuel was been added, 4.5% over standard did seem quite low.
Wideband should be ok, only done about 500 miles. Am using it to simulate the narrowband aswell and closed loop its running around the 14.7 mark so should be functioning correctly.It doesn't specify turbo or NA, its more to give a flavour for the different areas of a map and why you might target a different AFR at different fuel settings. Turbo's affect timing more significantly than fueling. It is the interaction between timing and fueling that often causes confusion.
Below is a graphical way to look at AFR's:
On a turbo car you go to 12 to 12.5 but you are still in that peak HP hump area. Ultimately, a car fuel management system is very simple as you have 4 cylinders with different CR's and only one MAF, one lambda and generally common timing. This is before you add in a constantly changing environment and differences in fuel injectors. People like to argue over it but it is a rough science.
If your car is 10.8 at peak HP (between 6K and 6.8K?) then it is about 10% too rich. Even in the greyness of tuning you would find very few people arguing for that AFR when using decent petrol.
Before you start taking out fuel, when your MOT comes round and if you know the people, check your installed sensor against the testers. Handy way to get yours checked once a year ;-) Good engineers rule of thumb is before changing a system, always double check your instruments readings first. (Measure twice, cut once as the carpenter says)
Cheers,
Jim
Seen a few things recommending a/f of around 11.7 on a turbo car, 12.5 n/a which is the reason i ask.
In terms of ignition its retarding from standard by 2 degrees on 85% throttle from 4.5k to 5.5k and then 3 degrees from 5.5k upwards. With the richer mixture burning slower i was suprised to see the timing being retarded aswell. Maybe it was just set up mega cautiously origionaly? Im still learning all this stuff so threads like this are very useful to see different peoples experiences.
P
pulsarboby
Guest
i dont know much about tuning chris but ive never heard of ignition being retarded coming on to wot, if anything some tuners add too much ignition to boost the bhp readings on dyno, but in doing so you have a car thats not very drivable through the rev range.
this is one definate problem that a few people have had from no.....names lol and no its not ed;-)
perhaps as you say they were being ultra safe when mapping the car:?
this is one definate problem that a few people have had from no.....names lol and no its not ed;-)
perhaps as you say they were being ultra safe when mapping the car:?
@Chris. part of the problem with the internet is in the states they have rubbish fuel whilst most of us in the UK run Optimax or equivalent. They can be seriously knock limited on their "pump gas" whilst we in blightey are not. This can lead to people talking about all sorts of safety margins and knock issues that we don't see.
Though not great here is a typical discussion on the internet:
http://www.sr20-forum.com/tuning/16...82-lambda-why-you-should-too-all-welcome.html
I think its worth pointing out that an average target AFR needs to be checked against the max and min value as well. For example, if your average seems okay but your max is too high then it might be worth considering targetting a lower average AFR.
Your lamda sounds new which i good. Do you have a timing gun? have you checked your measured IGN value equals what you read with the gun?
Your IGN reading sounnds sensible. As you are running more boost over stock then you will have to retard the ignition. This is normal and as we don't know what your base map really is this amount is in the range.
Are you planing too map the car yourself?
Though not great here is a typical discussion on the internet:
http://www.sr20-forum.com/tuning/16...82-lambda-why-you-should-too-all-welcome.html
I think its worth pointing out that an average target AFR needs to be checked against the max and min value as well. For example, if your average seems okay but your max is too high then it might be worth considering targetting a lower average AFR.
Your lamda sounds new which i good. Do you have a timing gun? have you checked your measured IGN value equals what you read with the gun?
Your IGN reading sounnds sensible. As you are running more boost over stock then you will have to retard the ignition. This is normal and as we don't know what your base map really is this amount is in the range.
Are you planing too map the car yourself?
Never thought about that with the american fuel, one of the more in deph things i was reading was from an american writer though not on internet. Havent data logged my a/f right through the rev range yet and im only really keeping a close eye when WOT to make sure its not running lean tbh.
Will have to check but think the emanage blue will only show what the ignition is altered by and not the actual. Theres a 1 degree +/- error aswell.
Am planning to do some mapping on it, looking to get a knocklink sometime soon than i'll have pretty much all i need to go. Have also got an emanage ultimate here i may swop for the blue as it has alot more facilities or may look into the nisstune stuff.
Bob, have you still got the emanage that came off the Hiteq care you had recently and what injectors was it running. If you have is there any chance of getting the settings off it to see how it was mapped? Its basically the exact same spec as mine but running a bit more boost.