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dx4picco

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  1. Like
    dx4picco reacted to koracing in Translating Fuel Injector Data   
    Dead time has the largest affect at idle or in other areas of the map where the effective pulse width or duty cycle is very low as the dead time in these cases will often be much higher than the calculated effective pulse width.  Actual pulse width commanded to the injector is the addition of injector response time aka dead time and calculated effective pulse width.
    Usually provided data is not 100% correct unless it was set up with the same ecu (so it has the same driver hardware).  It is very critical also to make sure you have the correct engine displacement data, and injector flow value entered.  You also need to be sure you're setting the dead time for the differential fuel pressure the engine is operating at. 
    If you're unsure if your deadtime is correct, and if you want to check it - do the following after warming up the engine fully and having no more warm up enrichment active (or any other active fuel trims ideally):

    1. tune idle to run right on lambda target with closed loop off or as close as you can. (for example 1.000 lambda)
    2. Change lambda target to 0.9 lambda and see what value the afr goes to.  If dead time is correct - the new lambda value will match target.
    At this point if it is not hitting the new target the dead time needs to be corrected.  The following is what I do, and may not be the best way, but has worked well for me:
    A. If when changing from 1.0 lambda to 0.9 lambda target the AFR undershoots - does not go all the way down to 0.9 - you have too much dead time and not enough resolution on the VE table.  Reduce dead time and retune the VE table to match target.

    B. If when changing from 1.0 lambda to 0.9 lambda target the AFR overshoots - goes past or below 0.9 - you have too little dead time and too much contribution from the VE table.  Increase dead time and retune the VE table to match target.  
    Rinse and repeat.
    Ideally you will do this at multiple voltages to generate a correct curve, but being able to apply multiple voltages to a car's injectors, ecu, and ignition while it's running isn't something everyone has the ability to do, and in the real world you're usually going to be operating at roughly the same voltage plus or minus a volt 99% of the time, so it's certainly critical at a minimum to get the dead time right at nominal operating voltage.  If you have an adjustable regulator you can also perform this same test at multiple differential pressures to get a good 3D dead time table, it just takes time.
     
    Having correct dead time makes all the tuning go quicker afterwards as all changes that are predicted to be needed based on AFR readings will be more accuately applied, as well as all fuel calculations and corrections the ecu is using will be applied to the actual effective injection pulse.
     
  2. Like
    dx4picco got a reaction from atlex in M5X Pnp Road Tuning   
    you don't need any of these to run modeled equation. only one of my cars have FP sensor.
    Leave the traditional fueling alone, and get into the last century with modeled one.
  3. Like
    dx4picco reacted to Adamw in Jaguar XJS v12 1988   
    Im not really here to support a competitor product so I cant waste too much time diagnosing, but I cant help feeling the variability you are describing sounds more like a "floating input" issue or perhaps a highside/lowside drive incompatibility.  So I would dig a little deeper in this area before abandoning the ecu.  I believe the Maxx GP outputs are low side drive only and dont have internal pull-up resistors or flyback diodes, and the fan controller internal circuit is really anyone's guess.  Have you connected a pull-up resistor to the output?  If not, I would suggest trying a 1.5Kohm resistor connected between +12V and the output wire going to the fan controller.   A brief description of a floating input here:  https://www.mouser.com/blog/dont-leave-your-pins-floating
    Be aware also, the commanded duty cycle in many OEM software and scantools etc is based on "percent high" (as are most multimeters), whereas many aftermarket ECU's with low side drive outputs, the commanded duty is "percentage low".  So you may find 90% in the OEM ecu is equivalent to 10% in the aftermarket ecu - assuming it has a pull-up etc.     
  4. Like
    dx4picco reacted to Adamw in Adding traction control to G4X Storm on a Gen 3 Dodge Viper   
    I dont particularly like "intercepter" type devices, they have to make a lot of assumptions about injector and ignition events, dwell times etc and since they dont have any of idea of the scheduling the ecu is doing, there will be conditions under which they will be commanding sparks and or injection events at the wrong times.  Especially during limiters and fast transients.   
    One thing you could try is a more basic traction control with the Storm.  The storm will still calculate slip if you have driven and driving wheel speeds assigned.  You can use the open loop power reduction part of the power management function to control slip with retard and cuts. 
    A quick explanation with a crude example below: 
    Say I wanted to allow about 7% slip in 3rd gear and above.  The open loop Ign trim will start to retard ign when slip goes above 5%, the retard will ramp up to a max of 30deg by 7% slip.  If slip continues to increase above7% with max retard, then the open loop cut will start adding cuts, up to a max of 40% cuts at 10% slip.    

  5. Like
    dx4picco reacted to koracing in SR20 running rough   
    Got online with @CodySoFine last night and got it to idle fairly stable.  His IACV seems to bypass a bit more in the fully closed position than excpected, but ultimately turning on the closed loop idle, changing the base position table down quite a bit, and then enabling idle ignition control was able to get the idle pretty stable and the AFR to act pretty stable around idle.
  6. Like
    dx4picco reacted to CodySoFine in SR20 running rough   
    Yes. My regulator has a gauge on it and I can visually see the pressure is not fluctuating.
     
    @jdniss
    I had some issues with that as well but I bought a new O2 sensor for my wideband and my numbers seem to be much more consistent. It's off by maybe .2-.5 lambda but certainly nothing I'm actively concerned about or attributing to the cause of my issues.
    One thing I do find suspicious is the timing table. I've watched videos of other people setting up links on their SR20s and in the trigger timing table their offset is -40 to -100 to get the timing marks in the correct spot but I had to give my car +20 degrees to get it on the right mark. This is a brand new motor and I've verified my cams are timing correctly about 6 times in addition to the machine shop verifying it so I know my motor is timed correctly but I'm not sure why my offset is so wildly different to other peoples. This could have something to do with it but I'm not sure. I'll recheck timing for the 7th time and report back if I figure anything out.
  7. Like
    dx4picco reacted to Adamw in WRX V11 - Antilag guidance   
    Sorry, a bit of a brain fart in that last example.  Try below.  

  8. Like
    dx4picco got a reaction from Synthstain in CAN Wideband into G4X StormX   
    AEMnet + to can high on ecu
    Aemnet - to can low on ecu
  9. Thanks
    dx4picco reacted to Adamw in WRX V11 - Antilag guidance   
    I dont have much experience with fuel cut apart from some brief testing in a not-really-suitable road car when we first added it.  I think the general idea is generally just to add enough fuel cut to keep EGT under control, and I suspect likely will need a lot more throttle/air also.
  10. Thanks
    dx4picco reacted to Adamw in WRX V11 - Antilag guidance   
    I would have the tables set up more like below.  So, any more than 1% pedal movement the ALS is removed. 
    I have the ISC override at 20% below 1%APS and by 2% it fades back to normal idle position.  The cut and retard are also removed over the same APS range. This may give a quite abrupt dip or surge in power so these axis breakpoints will likely need to be tweaked based on logs and how it feels. 
     
  11. Like
    dx4picco reacted to SidewayzSkyvia in Wrx11x low Rev limit/won't rev?   
    I ordered an aem 0300 kit. So I'll be able to log lambda here soon. 
    And I've located a different cam angle sensor to try out. I'm still leaning towards it being a cas issue as when the engine isn't up to temp it will usually rev a bit higher, up to around 5k. When it gets up to temp it won't go over 3k or so. 
    I've also made the changes Adam suggested to the tune. Once the new wideband gets in I'll try it with those changes. If it's the same thing I'll put a different cas in and hope for the best. 
  12. Like
    dx4picco got a reaction from Vaughan in R35 GTR   
    Vaughan, to my knowledge there is a bridge pipe, maybe like 20mm diameter at the back of the stock upper intake manifold to link both banks. 
  13. Like
    dx4picco got a reaction from Japtastic141 in First attempt at Fuel Map - Road Tuning R32 GTR RB26   
    cold/warmup idle 300°C, warm idle 450-500°C as the exhaust is still warm from the previous running
  14. Like
    dx4picco got a reaction from koracing in First attempt at Fuel Map - Road Tuning R32 GTR RB26   
    cold/warmup idle 300°C, warm idle 450-500°C as the exhaust is still warm from the previous running
  15. Like
    dx4picco got a reaction from kiwi-racer in ABS CAN ID   
    install g4+software too to open the map
  16. Like
    dx4picco got a reaction from Takuto0187 in Accidentally deleted mixture map. please help   
    as far as I know mixture max takes into account the active log / the one opened in the log windows for example. so it correspond to your expectation of only using the last run, if the logs are separate. 
  17. Like
    dx4picco got a reaction from DenisAlmos in Idle conversion stepper to solenoid Subaru WRX   
    I would hazards guess you should put a new age TB at least (or with manifold as it has same head pattern as V5-v6).
    New age TB needs only one aux and PWM.
  18. Like
    dx4picco got a reaction from Volcom86 in Why would my boost spike mid range and fall   
    from my experience, shortening the WG arm/ more preload is detrimental to what you are trying to solve. boost control will be even harder down low but little improvement up top
    more spring would help (if duty doesn't) provided the turbo isn't maxed out like Vaughan said. 
  19. Like
    dx4picco got a reaction from koracing in Link G4X running lean with hot start + unstable idle (subaru impreza V8)   
    for the lean hot startup it is due to heat soak. to combat that, you can use a 4D fuel table with IAT as X axis and engine runtime as Y axis. for higher IATs and for a given time, put something like 10% enrichment and decrease after lets say 60 second to 0 in 30 seconds.
  20. Like
    dx4picco reacted to castillaricardo in 350Z - Supercharged/E85 cold start   
    You’re welcome. I hope it helps.
    Around here our 91 is E10. I think you could make your 0% row 40% of your 100% row, and interpolate in between for a closer guesstimate; of course trial and error is the only way to tune crank enrichment.
  21. Like
    dx4picco got a reaction from Cr4ig in How to adjust dwell times.   
    I believe you have as column axis RPM. and line axis voltage, do you?
    in that case you can put the values you have in each column.
    Or modify your table axis to get your expected format.
  22. Like
    dx4picco got a reaction from Wuzie123 in G4+ Fury dash options for offroad truck.   
    as long as you are sure this a a standalone dash version, and not their PDM display type of things then yes you will be fine. 
  23. Like
    dx4picco reacted to CDL.R33 in Link g4 pnp eccs circuit   
    Hello!
    I contacted the support, sent my ECU to their EU HQ. They sent it to NZ for repairs and i got i back today. 
     
    The problem stated on the service report was that the MOSFET was still ok but some other fault on the bottom board was detected.
    They replaced the bottom board with a newer version and made it fit the G4 Top board.
    Everything was preformed under warranty.
     
    This suppport on a 10 year old ECU is not what i would have expected.
    Big thank you to Link! 
  24. Like
    dx4picco reacted to fantapants in old mans ke70, 3sge itbs, irs and xtreme g4x   
    heya peeps.  
     
    my name is Pat. and this be lolla.
     
    my skills reside in the fabrication side of things, ecu and trickery are not my talent. lol.  this build was a long time coming, having owned the car since 2008.  i got very sick in 2014, being left permanently disabled.  the car build became a rehab and mental health project as much as anything.
     
    she has a mongrel 3sge gen 4 beams engine.  converted to rwd using a mix of factory gen5 bits and custom fab.  using blacktop 20v throttles and now a link xtreme g4x.  this ecu was made possible by a good friend derek who convinced me to abandon my old adaptronic lol.  We also gave the fuel system a birthday with new inj and fuel pressure snesors.  Running of his 4age blacktop tune, it was remarkably well behaved.  His engine is a very stout 1.6, so we figured pretty close in total throughput to the bigger 3sge, using the same throttles, similar vvti etc.  it wasnt until we did some real hard low load stuff on the road tunning that we saw big changes needed in the tune.  She also has a nissan s15 rear suspension cradle and irs fitted, with s13 hubs for the 4 bolt (the wheels were always staying).  This was done using a fabricated chromemolly cardle narrowed o fit the stock diff width of 1410.
     
    Currently im working my way through learning about canbus .... trying to get realdash up and running to replace the janky cheap windows tablet i have currently.
     
     



  25. Thanks
    dx4picco reacted to Adamw in close loop boost control   
    You can vary the target with APS as you have set up.  Set up the control so that it only moves into stage 2 when you are somewhere close to the minimum achievable "spring pressure boost".  The lowest value anywhere in the target table should also be the same "minimum achievable spring pressure boost".  In stage 2 the duty cycle will still mostly be coming from the wastegate DC table just like it did in openloop mode but with corrections added depending on how far off target you are. 
      
    In stage 3 the actual DC value applied to the wastegate comes from "Base DC"  + Proportional correction + Integral correction.  If the base DC mode is set to "Stages 2-3" then the "Base DC" part is coming directly from the base DC table.  If set to "Stage 2 only" then the "Base DC" part is fixed at the last base DC that was being commanded from the table when you left stage 2. 
    I would suggest base DC mode "Stages 2-3" based on the shape of your base DC table.  You have a big change in your base DC table between 5&6000RPM so likely closed loop will need to do less work with the variable base dc coming from the table through the whole rev range. 
    I dont think I have ever needed to use the "Stage 2" base DC mode but I suspect there are applications where there is some other factor involved that causes the DC required to reach target quite variable, but once you are on target the control requires less variation. 
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