Håvard Karlsen
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Posts posted by Håvard Karlsen
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Where do i find that file?
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Hello, i have wired up can Lambda to my snowmobile-engine. I have followed the instructions for software in the help section.
I have not started the engine, but i have a handheld starter and it turns it at 650 rpm. Gauge( Lambda1 shows nothing on my pc, and sensor does not heat up.
Any ideas?
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32 minutes ago, Adamw said:
You can turn it off but I suggest you leave the target table on, it doesnot need a AFR sensor, the table multiplication will still work without a sensor connected.
I see
Thanks
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13 hours ago, Adamw said:
Ok, below is a basic made-up example.
To explain, fuel table 1 is the main VE table, this basically tells the ecu how much air the engine is inhalling (assuming it was naturally aspirated). If you set the fuel load equation source to "MAP", then this table is multiplied by MAP in the background, so even though it only has TP on the VE table axis, if you double the manifold pressure the ECU already knows there is double the air going in and therefore adds double the fuel. The calculated fuel pulse width is also further multiplied by the Lambda target table in the background, so this compensates for the fact that you normally want a richer mixture at say 200Kpa and 100%TP, than you would want at 100Kpa and 100%TP.
Since the turbo creates back pressure on the exhaust side and may effect volumetric efficiency, you may find that as you increase boost more and more the fuel mixture will start to drift off target, to fix this you have the 4D fuel table. The 4D fuel table is an "adder". So if you have "10" in a cell it adds a further 10% fuel in that region, if you have a "-10" it removes 10% fuel in that region. You would set up this table with MAP Vs RPM, usually most of this table will be zero and you will only have to tune a few cells in the high RPM/High boost corner to get the fuel mixture right at all boost levels you intend to run.
To tune these two tables, you start with the 4D table all set to zero, run engine on lowest boost possible (wastegate spring only) and tune the main VE table all over. Then increase boost say 50kpa and run engine, through whole RPM range, adjust the relevant row of the 4D fuel table if it needs some fuel added or removed at the top end. Repeat at higher boost levels until you are at the maximum you intend to run.
After the ecu has calculated the correct fuel volume that needs to be added, then you can choose how you want to split that between primary and secondary injectors. Again this is very flexible, these can be the same size or different sized injectors, you can have both injectors spraying half the fuel each or you can have all fuel going through the secondary inj at high RPM or whatever you like. In the example below I have primary and secondary injectors both the same size. I have all fuel going through the primary below 100Kpa MAP, then above 100Kpa I fade in the secondaries and by 180Kpa I have half the fuel going through the primary and half through the secondary.
Do i need the lambda target table. I would like to have no afr sensor controling the map. Can it be done without it?
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9 hours ago, Adamw said:
Ok, below is a basic made-up example.
To explain, fuel table 1 is the main VE table, this basically tells the ecu how much air the engine is inhalling (assuming it was naturally aspirated). If you set the fuel load equation source to "MAP", then this table is multiplied by MAP in the background, so even though it only has TP on the VE table axis, if you double the manifold pressure the ECU already knows there is double the air going in and therefore adds double the fuel. The calculated fuel pulse width is also further multiplied by the Lambda target table in the background, so this compensates for the fact that you normally want a richer mixture at say 200Kpa and 100%TP, than you would want at 100Kpa and 100%TP.
Since the turbo creates back pressure on the exhaust side and may effect volumetric efficiency, you may find that as you increase boost more and more the fuel mixture will start to drift off target, to fix this you have the 4D fuel table. The 4D fuel table is an "adder". So if you have "10" in a cell it adds a further 10% fuel in that region, if you have a "-10" it removes 10% fuel in that region. You would set up this table with MAP Vs RPM, usually most of this table will be zero and you will only have to tune a few cells in the high RPM/High boost corner to get the fuel mixture right at all boost levels you intend to run.
To tune these two tables, you start with the 4D table all set to zero, run engine on lowest boost possible (wastegate spring only) and tune the main VE table all over. Then increase boost say 50kpa and run engine, through whole RPM range, adjust the relevant row of the 4D fuel table if it needs some fuel added or removed at the top end. Repeat at higher boost levels until you are at the maximum you intend to run.
After the ecu has calculated the correct fuel volume that needs to be added, then you can choose how you want to split that between primary and secondary injectors. Again this is very flexible, these can be the same size or different sized injectors, you can have both injectors spraying half the fuel each or you can have all fuel going through the secondary inj at high RPM or whatever you like. In the example below I have primary and secondary injectors both the same size. I have all fuel going through the primary below 100Kpa MAP, then above 100Kpa I fade in the secondaries and by 180Kpa I have half the fuel going through the primary and half through the secondary.
Thanks. I will take my time and try to learn this. This forum is very good!!
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On 1/24/2020 at 8:59 PM, Greg W said:
We use the link on turbo bikes, dual injectors , big cams , low compression , ITB,
Using MAP/BAP X over base setting with TPS/rpm fuel table , staged secondary injectors and MAP based secondary staging table
would this do what your wanting ?Can you explain this better for me? I will not use closed loop afr or any afr input at all. Just for gauge and logging. Twostrokes is hard du auto-tune.
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On 1/24/2020 at 9:34 PM, Adamw said:
I would probably lean more towards CJ's first suggestion which is to have main fuel control based on alphaN, but with a 4D MAP/RPM overlay added for any adjustment needed due to varying boost levels or the effect the turbo has on the scavenging (on a 4 stroke you often dont even need this 4D table as MAP is taken care of in the background). This way will make your life easier than your original requested strategy. With your requested method, anytime you want to change the injector staging or the split between primary/secondary, you would have to almost totally re-tune both fuel tables to get the mixture right again. With the 4D method you can experiment with injector staging/split after tuning the fuel tables without consequence.
Do you have a sample file. How it is done? Settings etc?
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Can you help me setting this up? Do you know any links for «how to»? I have been taking courses for Link ecu, but the staging with tp/rpm base map i can not find. Every example have map insted of tp in the x axys....
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I have a 3 cyl two-stroke engine. It have turbo and two injectors for each trottle (3 trottles) I want to drive primary injectors with tps/rpm table and secondary injectors with a map/ rpm table. Is this possible? Is there a better way to control the injectors? The engine have a very weak manifold vacuum.
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Two-stroke
in G4+
Thanks for helping
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Two-stroke
in G4+
This engine will have rev limit at 10.000rpm
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Two-stroke
in G4+
Nice
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Two-stroke
in G4+
What engine is it Race Jase?
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Two-stroke
in G4+
I must make a trigger wheel. It must be 128mm OD and 80mm ID. How many teeth must it have? How big should they be, and what distance between them?
Thanks
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Two-stroke
in G4+
Looking at your pic
Your mag has 3 spaced pickups (magnets) at every 120 deg your stock ecu can work out tdc from this but the link can not
You have the same problem we had so there was a couple of options, either add another sensor somewhere on the engine so you can run a trigger and home sensors so the link knows when a tdc event is or the way i went is making a multitooth/missing trigger wheel this worked for us no problem on our tripples.
Jase
how does link work out tdc? Must the missing tooth be at cyl-1 tdc?
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Two-stroke
in G4+
The flywheel have 3 "teeth" on it
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Two-stroke
in G4+
How small can i get a trigger wheel? Will it not work with the stock pick-up? ( Arctic Cat Thundercat 1000)
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Two-stroke
in G4+
Yes, you should download the software and have a play if you haven't done so already:
I know it should work fine if your engine is a standard even 120° firing angle, however if you have one of those odd engines where one piston comes up as two go down you might have to get creative with the configuration and wiring.
Thank you!
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Two-stroke
in G4+
Can i use the G4+ on a triple twostroke? Are there settings for two strokes in the software?
Thanks 
arctic cat
in Snow
Posted
What injector timing do this twostroke use? I have Link storm on my AC tripple turbo. In have no idea what settings for injector timing