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  1. M

    10/23 Raptor Video

    So if you go back a few of my post ago, I mentioned that on some SI ECUs it is possible set or force minimum values, 2ms as an example injector open pulse width. I've seen it, even some OEMs have minimum fall back value. You may or may not see it depending on which registers are being...
  2. M

    10/23 Raptor Video

    So I think I understand where the disconnect is... So need to revisit the multi-processor approach. Lets stick with main processor and I/O co-processor for now. The I/O co-processors handles synchronous events such as injectors and spark (SI example), based on crank angle. When ECU starts up...
  3. M

    The A-4 Skyhawk

    Nice plane. From memory, I thought it under performed for installed power?
  4. M

    10/23 Raptor Video

    I was referring to high crankcase pressure perhaps hindering oil return flow. You'd be surprised how much blow by can be generated on a failing engine. As others mentioned, hard to generate a vacuum without a throttle. If PM thinks he is generating a vacuum, well I guess it's about par for the...
  5. M

    10/23 Raptor Video

    The Motec was reporting it's reality of fuel flow (with strange offset), yes the engine wasn't running. Somehow an error or offset got introduced along the way. When PM first hired people to do initial calibration, I'm reasonably (99%) sure that the 20mg wasn't there. But along comes PM to do...
  6. M

    10/23 Raptor Video

    Well, yes and no. It really depends on how software is written. Some simple examples are IAT (inlet air temperature), oil pressure, ECT (engine coolant temperature), MAP (manifold absolute pressure)... and so on. Once the ECU starts up, performs sanity checks, and fires up OS, these analog...
  7. M

    10/23 Raptor Video

    OK, my bad. Guess PM doesn't believe in "As Built" documentation. Don't want to speculate too much, but wonder what his crank case pressure was like? There was enough elevation change for gravity drain, if lines are sized correctly. Most PCV systems from factory are barley adequate, with his...
  8. M

    10/23 Raptor Video

    That 20mg of fuel is explainable. Some offset or minimum fuel got "baked" into tune or tOOne. A simple example is, on SI engines some ECUs have minimum injector open time setting. So, set it to say 2.5ms, every time injector opens it will be for that time or greater, regardless of internal...
  9. M

    10/23 Raptor Video

    You are correct, if built as per 3D assembly in video, then design is not even half baked. The design appears to use "sealed ball bearings" as replacement for actual or real seals. If common sealed ball bearings, then it's only a question of when, not if, those seals fail, as intended design is...
  10. M

    Nikasil Cylinders

    If you're asking why change from steel or cast iron to aluminum jugs with special coating(s)? Aluminum piston's thermal expansion coefficient is higher than that of steel or cast iron. Or it expands (grows) at a greater rate than the bore it's moving up and down in. To account for this, you'd...
  11. M

    10/23 Raptor Video

    Very generically, the greater expansion ratio (16+) of diesels, also has a significant impact on EGTs. The Raptor engine is listed as 17:1 compression ratio. A modern gasoline turbo 4 banger will be in 9.5 - 10.5 compression ratio range by comparison. Don't think it's the case anymore, but...
  12. M

    10/23 Raptor Video

    It's called flo-vis in those circles ->Link Paint
  13. M

    Water Injection for Industrial V-Twins

    I'd be concerned about just running H2O on NA for said purposes... When RH is high, you'll likely just puddle somewhere. Go with water/methanol mix (windshield washer fluid). Yes BTU capacity is lower, but you are also adding fuel with higher octane. Spiking windshield washer fluid with "Heet"...
  14. M

    Water Injection for Industrial V-Twins

    See link Nozzle . At the top of the page is the one used by many kits (even on aircraft).
  15. M

    Water Injection for Industrial V-Twins

    There are good Tech papers from WWII era testing (NACA and others) out there. Keep in mind, the higher the RH (relative humidity), the more you have to lean on pressure to get droplet size down. With smaller droplets you effectively increase surface area, which interns helps with phase change...
  16. M

    Spark redundancy.

    It's all good. I generally have a self imposed X beer cutoff for posting LOL. I've only looked at Speeduino a few times, and that was at crank decode and speed density (SD) portions only. Crank decode AS IS, is not capable of detecting misfire due to lack of velocity change. SD is close but...
  17. M

    Spark redundancy.

    Sorry. if I offended. My comment on "automotive grade" micro, had to do with ESD, vibration, in some cases flash endurance, injection current and so on, including temperature range (-40 to 125C). Industrial can be surprisingly wimpy by comparison. As far as CanBus, it is a low overhead to...
  18. M

    Spark redundancy.

    Ok - got it. Looked at website under fuel maps ( Link ). So SDS fuel injector pulse width = Curve_A + Curve_B + Curve_C + Curve_D. Curve_A, being "base fuel" or RPM based lookup values. Curve_B, being "MAP (manifold absolute pressure) enrichment" based on lookup values. Curve_C, being "IAT...
  19. M

    Spark redundancy.

    Yes that is correct! I have a thing about having long and short term trims slightly negative, so if a sensor craps out, there is additional fuel there, due to going open loop. It's good practice. Also don't like huge variations in VE table to mask lack of correct injector calibration, again good...
  20. M

    Spark redundancy.

    Well this is a bit of a apples to oranges thing. I was referring to a automotive closed loop ECU with drive by wire (DBW) throttle, functioning AC and all amenities. I'm well aware of SD and MAF theory, and how that gets converted (calculated) to injector pulse width. Tuning for WOT (wide open...
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