tonino Posted December 20, 2011 Share Posted December 20, 2011 hi my DVA engine has been mapped by dave walker this summer. for some reasons, i have to change my exhaust (full system). i know i'll have to remap the ECU to get the best of my engine, but going back to emerald doesn't sound good to me (they are very nice people but the trip from france to norfolk is a pain in 🙆🏻 ) i was toying with the idea of buying a wide band sensor and set up the ECU to run on adaptive mapping. can you please tell me if i am talking BS or if you think it could be a good solution? what are the pros and cons of adaptive mapping VS rolling road mapping? merci Link to comment Share on other sites More sharing options...
CageyH Posted December 20, 2011 Share Posted December 20, 2011 It's what I do. Toulouse is even further away. You just need to make sure you have the good air/fuel ratio settings, but you can copy your original map to a spare slot. Link to comment Share on other sites More sharing options...
catastrada Posted December 20, 2011 Share Posted December 20, 2011 1. You could search and find someone that can do this in your area 2. Like we did ealier this year, we built a small owner group, have Steve Greenald (Track and Road) fly to Strasbourg and map our cars. We rent a rolling road installation. We shared to cost and as a result it costed much less than going over the Channel with our trailers. Edited by - Catastrada on 20 Dec 2011 20:17:19 Link to comment Share on other sites More sharing options...
tonino Posted December 20, 2011 Author Share Posted December 20, 2011 thanks guys i have a tuner who is a few miles away from me , but he has never done a emerald mapping before. the fact he seems to be reluctant to do it make me think a won't get the best from the mapping session.but maybe it could still be better than going for the 'self mapping' way... Link to comment Share on other sites More sharing options...
dannylt Posted December 20, 2011 Share Posted December 20, 2011 What is he used to using? The Emerald is easier to use than most - and a professional shouldn't have any issues just fixing the fuel map. Link to comment Share on other sites More sharing options...
CageyH Posted December 21, 2011 Share Posted December 21, 2011 The self mapping works well. My car passes the CT on a self mapped map. You have a good base map to start with, and you will probably only be looking at a minor adjustment depending on what you are changing from/to. Link to comment Share on other sites More sharing options...
charlie_pank Posted December 21, 2011 Share Posted December 21, 2011 Emerald self mapping is excellent - worked really well for me with an LC-1 wideband. Really simple to set up, eliminated some flat-spots and passed emissions no probs. Let me know if you need specific help... Link to comment Share on other sites More sharing options...
tonino Posted December 21, 2011 Author Share Posted December 21, 2011 thanks for your answers. the new primaries will be a little bit bigger and swapping from 4/1 to 4/2/1. adaptive way will be cheaper and more convenient than a RR session... cageyH, did you manage to go through french emission test without cat? charlie, will get in touch soon, thanks! Link to comment Share on other sites More sharing options...
CageyH Posted December 21, 2011 Share Posted December 21, 2011 No - you will need the cat. It was close without, but the cat made all the difference. Link to comment Share on other sites More sharing options...
skydragon Posted December 21, 2011 Share Posted December 21, 2011 Out of curiosity, what range of AFR targets do you use ? Link to comment Share on other sites More sharing options...
charlie_pank Posted December 21, 2011 Share Posted December 21, 2011 From memory 14.7:1 is the optimum ratio for power & efficiency. At higher load and speed positions you increase it up to a maximum of around 15.5 to help with cooling. I'm actually really amazed that there hasn't been more interest in the self-mapping feature. There are still circumstances under which you might need a rolling road, but their frequency is much reduced. Edited by - charlie_pank on 21 Dec 2011 14:52:27 Link to comment Share on other sites More sharing options...
skydragon Posted December 21, 2011 Share Posted December 21, 2011 I think you've got that the wrong way round (?) and that would be waayyyyyyy too lean. I'd expect to see a AFR of around 12.8:1 - 13.1:1 at high rpm and loads Edited by - skydragon on 21 Dec 2011 14:58:09 Link to comment Share on other sites More sharing options...
charlie_pank Posted December 21, 2011 Share Posted December 21, 2011 Yep you're right, sorry, been a while! Link to comment Share on other sites More sharing options...
jackb_ms Posted December 22, 2011 Share Posted December 22, 2011 My engine has been mapped however there is some flat spots. Would the self mapping remove them? Does the Emerald needs to be connected to a computer or does it apply the changes automatically? Jack Link to comment Share on other sites More sharing options...
gundersen Posted December 22, 2011 Share Posted December 22, 2011 Quoting charlie_pank: I'm actually really amazed that there hasn't been more interest in the self-mapping feature. There are still circumstances under which you might need a rolling road, but their frequency is much reduced. As far as I can read, self mapping is only good for adjusting fuel mixture. And while that is all good, isn't the power to be found in the ignition timing? Link to comment Share on other sites More sharing options...
Doug Posted December 22, 2011 Share Posted December 22, 2011 Using an Emerald myself, I suggest you ring Dave Walker and explain the problem. He'll have a copy of your map and will probably be able to suggest the best way forward. Link to comment Share on other sites More sharing options...
charlie_pank Posted December 22, 2011 Share Posted December 22, 2011 Emerald self map: no it doesn't need a computer attached to it while it is self-mapping. There are different modes within self-mapping too. You DO however need to tell it to self-map with a computer and you need to configure it to work with your wideband lambda probe. Yes, it will only self-map for fueling not ignition-timing. So if it's ignition that you want to tweak you'll need a knock-sensors and a rolling road. I don't think that the ignition timing is affected by most external mods nearly as much as fueling hence my comment that the number of circumstances under which you'll need a rolling road remap is reduced. Link to comment Share on other sites More sharing options...
gundersen Posted December 22, 2011 Share Posted December 22, 2011 Quoting charlie_pank: I don't think that the ignition timing is affected by most external mods nearly as much as fueling hence my comment that the number of circumstances under which you'll need a rolling road remap is reduced. Aahh yes, you might very well be right there. I don't have a clue as to what affects timing and what affects fueling My research into self/adaptive mapping has been with the goal of avoiding a trip to the rolling road by doing the tuning myself, and it seems that this is not possible because you need the torque figures to tune ignition timing correctly. Link to comment Share on other sites More sharing options...
tonino Posted December 22, 2011 Author Share Posted December 22, 2011 guys, you may be interested to know what dave walker advise me : It is most likely that the new exhaust will change everything as far as the map is concerned. You can buy a wide band and use the logging facility on F12 to log the mixture during a power run. If you can find a rolling road that will run your car while you alter the mixture you should be able to get it mapped okay. We have seen good results from the Tech Edge wide band kit. The adaptive mapping wi8ll not work well enough on full power runs as the engine accelerates too quickly. Logging and manual changes to the map is the only way to do it. sounds like i'll have to trip to emerald once again... Link to comment Share on other sites More sharing options...
charlie_pank Posted December 23, 2011 Share Posted December 23, 2011 I think there may be some confusion here. Using the adaptive mapping function, the ECU logs engine speed, load (and other factors - coolant temp, MAP etc...) and the AFR reported by the wideband. In the first instance the fuel for a given load/speed site is determined by the base map you put in. You also enter a target AFR map and the ECU compares the actual AFR with the target AFR to make the adjustments required. The mode that I found most helpful was one where you could attach a laptop and look at the adjustments that were being applied to the base map at any point and choose to cement them into the base map or leave them as live adjustments. If you go to a rolling road, you'll use their tools to log the load and speed and their wideband lambda probe to log AFR, you'll get the results for each load/speed site and then make the appropriate adjustments to the base map by hand. 1. Why would there be any reason to suspect that your wideband lambda probe recorded data slower than one that a rolling road bought? 2. If you think that the ECU can't make decisions about fueling fast enough, how can you trust it to run the management of your engine, adaptive mapping or not? Link to comment Share on other sites More sharing options...
gundersen Posted December 23, 2011 Share Posted December 23, 2011 Quoting charlie_pank: 1. Why would there be any reason to suspect that your wideband lambda probe recorded data slower than one that a rolling road bought? I don't know if this is the case, but engineers optimize designs to a given scenario/specification. Since your normal lamba probe is only used a cruising speeds, there is no requirement for it to be reacting extremely fast. So if the engineers could cut costs in some way by making a slower design, I am sure they would do that. Where as the specifications for a lambda used at a rolling road would definitely be specced for fast response. That said, since both the Emerald and Megasquirt (and probably many others) have features for self tuning by adjusting the map based on logged data, it must work to some degree. I think the main issue with doing fuel adjustments this way is the inability to reach all cells in the map and the challenge of holding the load vs. rpm steady long enough to make a usable measurement for tuning. But you still has the issue of ignition timing, which I still don't see any way of doing outside a rolling road? Quoting charlie_pank: 2. If you think that the ECU can't make decisions about fueling fast enough, how can you trust it to run the management of your engine, adaptive mapping or not? I think most ECU's are plenty fast for making fueling decisions Link to comment Share on other sites More sharing options...
tonino Posted December 23, 2011 Author Share Posted December 23, 2011 not sure i really catch it, but adaptive mapping and self ajustment via wide band sensor are two diferent things. the adaptive mapping allows the ecu to adjust fueling while running (with help of AFR given by wide band sensor) but @ speed, sensor would not be fast enough and mixture should be wrong... self adjustment (on a RR obviously) with the help of a wide band sensor allows user to get the right AFR @load/speed and cement the values in a map that will be run in close loop. this is a kind of RR session, but using your own wide band (wich may be slower than 'profesional sensor') + you can't adjust ignition. so both are not complete solution to get a perfect map am i right?? Link to comment Share on other sites More sharing options...
oilyhands Posted December 23, 2011 Share Posted December 23, 2011 There are some very good reasons why a rolling road session is able to record lambda values at full throttle when adaptive mapping cant. On a rolling road the engine is pegged at a constant RPM/load this gives time enough for the lambda feedback for any particular load/RPM site to be examined and the fuelling and timing altered to suit. It is not done by logging and then manual adjustment, it is done in real time. On the road the engine will always be in transient when accelerating full throttle so each RPM site is passed very quickly. Adaptive mapping doesnt alter your fuelling, it makes suggestions for you to apply. Oily Edited by - oilyhands on 23 Dec 2011 11:35:57 Link to comment Share on other sites More sharing options...
gundersen Posted December 23, 2011 Share Posted December 23, 2011 This is my take on it 😬 Quoting tonino: the adaptive mapping allows the ecu to adjust fueling while running (with help of AFR given by wide band sensor) but @ speed, sensor would not be fast enough and mixture should be wrong... This is what closed loop is, so I suspect that most ECUs/lambdas do this well As far as I know, almost all modern cars run in closed loop when cruising. But the adjustments made when running closed loop are not persisted to the fueling map, so closed loop should not be used as a "fix" for a shotty map. Quoting tonino: self adjustment (on a RR obviously) with the help of a wide band sensor allows user to get the right AFR @load/speed and cement the values in a map that will be run in close loop. this is a kind of RR session, but using your own wide band (wich may be slower than 'profesional sensor') + you can't adjust ignition. When I refer to self adjustments, I mean what you can do at home without going to a rolling road. In this scenario you can't measure torque and it is difficult to created the rpm vs. load scenarios needed to "reach" all cells in the ECU map. The inability to measure torque makes it hard/impossible to tune your ignition map, as this is normally done based on max torque. If you go to a decent rolling road with a breaked dyno, you can measure torque and therefor adjust ignition. Quoting tonino: so both are not complete solution to get a perfect map Well going to a decent rolling road is the only way to get a perfect map as far as I know Edit: Damn, too slow. oily beat me to it Edited by - gundersen on 23 Dec 2011 11:43:53 Link to comment Share on other sites More sharing options...
charlie_pank Posted December 24, 2011 Share Posted December 24, 2011 Quoting gundersen: I don't know if this is the case, but engineers optimize designs to a given scenario/specification. Since your normal lamba probe is only used a cruising speeds, there is no requirement for it to be reacting extremely fast. So if the engineers could cut costs in some way by making a slower design, I am sure they would do that. Where as the specifications for a lambda used at a rolling road would definitely be specced for fast response. This is why you need to use a wideband lambda probe rather than your nomal narrowband one. http://www.innovatemotorsports.com/support/manual/LC-1_Manual.pdf section 6.5.1 states that 'the LC-1 is fast enough to distinguish individual pockets of exhaust gas. For many applications this will be too fast' Quoting gundersen: That said, since both the Emerald and Megasquirt (and probably many others) have features for self tuning by adjusting the map based on logged data, it must work to some degree. I think the main issue with doing fuel adjustments this way is the inability to reach all cells in the map and the challenge of holding the load vs. rpm steady long enough to make a usable measurement for tuning. The ECU is fast enough to control the fueling of the engine in all conditions. If the wideband lambda probe can detect 'individual pockets of exhaust gas', then which part of the system won't work? NB. Yes there are cells on the map that won't be touched by self-mapping in the absence of a rolling road. This doesn't matter at all, as the very fact that you've got no data on those points means you don't need them. You also don't need to worry that you might one day enter them because you just leave the 'self-map' activated so it'll fill in the gap if it ever enters that cell. Edited by - charlie_pank on 24 Dec 2011 15:41:05 Edited by - charlie_pank on 24 Dec 2011 15:41:56 Link to comment Share on other sites More sharing options...
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