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hugemikeyd

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Posts posted by hugemikeyd

  2. Visualizing Rotary Injection Timing

    in G4x

    Posted

    5 hours ago, Copyninja said:

    what was your rationale for running the above injection timings? 

    I was trying to take the Haltech chart and convert it to Link, which I tried taking each number and dividing it by 3 assuming that Haltech was using e-shaft degrees, but I was off. Rather than risk my engine, I will just stick with the 130 SOI, I am not trying to make tons of power so this should be fine for me.

    I find the trend to be going in the wrong direction, why would I want to inject fuel later as the RPMs go up, shouldn't fuel be going in sooner?

    haltech-inj-timing.PNG

  4. Visualizing Rotary Injection Timing

    in G4x

    Posted

    And 400/3 = 133, so he must be speaking in e-shaft rotation degrees. He also mentions something along the lines of "you have 270 degrees to inject fuel", 270/3 = 90 and 90 + 40 = 130!

    I think i finally get this about a year later :) 

  5. Visualizing Rotary Injection Timing

    in G4x

    Posted

    Bringing this back from the dead. Rob Dahm made a video where he goes in depth about various topics and one of those is Injector Timing. Here is the point in the video where it starts: 

    "You want fuel going in at that 400ish BTDC." 

    The above is confusing to me since Link only lets us adjust from 0-360, so is he really talking about 180 here? I assume he is speaking in terms of the degrees of rotation for the e-shaft whereas the Link is speaking in terms of the rotor?

  6. RX7 Stalling when Hot

    in G4x

    Posted

    I was able to make the static throttle body adjustable so I am able to make the necessary adjustments. However, for any RX7 owners out there using an aftermarket intake, make sure that your BAC valve is not just open to the engine bay like mine. If it is, it will suck in very hot air rather than colder air coming in from the intake. Also, this means that the Intake Air Temp is reading lower than what the BAC is pulling into the intake before it gets combusted. That very reason is probably why I was having an issue with getting the Charge Temp Approx table correct, it really depended on the temperature within the engine bay which is not measured, as opposed to Intake Air Temp and Engine Coolant Temp.

    I will play with the adjustment to get a stable idle with the Idle Control set to 0% at temp and report back what i see

  7. RX7 Stalling when Hot

    in G4x

    Posted

    I will work on that.

    If you take a look at the log, it keeps getting richer and richer as the Charge Temp increases, do i still need to adjust my Charge Temp Approx table to help compensate for that or something else? Maybe the closed throttle plate is what is making it run richer?

  8. RX7 Stalling when Hot

    in G4x

    Posted

    Link updated, no idea how that happened...

    are you saying that my throttle is too closed at rest? I can try and crack it a little bit to see if that helps. When i first got the car running it would idle at 2.5k, so i closed it a good amount to get it back down to a normal idle

  9. RX7 Stalling when Hot

    in G4x

    Posted

    I've been tuning the car more and was able to get things a bit better, but the car will still stall when hot and dropping back down to idle. I can see the RPMs drop to 500-600 and the ECU is unable to catch it before it's too late. This is more pronounced when hot, when the car is warming up or is initially at operating temp, the RPMs still drop, but the ECU can catch it. I have tried to adjust things to make it better, but nothing has worked so far. What else can i try?

    Tune and Log

  10. Rx7 FD grounding

    in G4x

    Posted

    FC owner here, I used a wire in ECU but I think it is the same in the end. I have the 2 grounds from the ECU (black) going to each rotor housing separately and the sensor ground (green) is isolated from the other grounds and is a closed loop with only the sensors and the ECU. The sensor ground should never be linked with the other grounds.

    With that said, is it possible that one or more of the sensors rely on the engine ground (black)? that would cross the lines which is not what you want.

  11. Visualizing Rotary Injection Timing

    in G4x

    Posted

    Awesome, I am so glad that I asked. I was confusing F in @Adamws diagram above as the TDC for the Injection timing based on the explanation in the manual: 

    • The units are degrees before top dead centre (BTDC) with reference to top dead centre between the compression and power stroke. This means 360 represents TDC between the exhaust and inlet stroke.

    But actually, it's C, got it. 

    Full disclosure, I was trying to take a dynamic End of Injection table from a competitor and make it work, but perhaps I should stick with the static 130 from the FD base maps...

  12. Visualizing Rotary Injection Timing

    in G4x

    Posted

    I want to better understand where in the 0-360 available injection timing for a rotary is visually:

    206-Tech-RotartVsPiston-009-rotarychart.

    The documentation states:

    • On Rotary engines Injection Timing Position can be adjusted from 0 to 360 degrees.

    • The units are degrees before top dead centre (BTDC) with reference to top dead centre between the compression and power stroke. This means 360 represents TDC between the exhaust and inlet stroke.

    Using the diagram above, would that mean Compression (second stage) represents 0 BTDC and Intake (first stage) is 180 BTDC?

  14. RX7 Stalling when Hot

    in G4x

    Posted

    4 hours ago, Adamw said:

    Is there an example of this in the log?

    the engine speed was ~500rpm, if i just have to play with the idle base position, i will make those adjustments

     

    4 hours ago, Adamw said:

    Smoothing is not really the issue, more so just need to pay more attention to what the numbers mean

    that makes sense, this is what i meant by smoothing. the map can't jump all over the place, it needs to be smooth and make sense not just in the active cell, but the ones that surround so that fueling doesn't become erratic. i was relying on the mixture map too much and not interpolating the changes to the surrounding cells, i will make sure to do that from now on, pretty silly to have to say that out loud now that i have said it...

    4 hours ago, Adamw said:

    Peak torque is somewhere around 25deg

    I actually didn't know that, makes a lot of sense why you would want that to be the max ignition for idle!

    I very much appreciate you following up :) 

  15. RX7 Stalling when Hot

    in G4x

    Posted

    Went for a drive this morning, ambient temps were about 10F lower than yesterday, so i stopped a few times and let it idle to get hot. It never stalled but did have some trouble staying alive at the very end.

    I have been relying on the Mixture Map feature a lot to adjust the fueling as i drive but i never applied a smoothing afterwards, was that one of my issues? Also, for the idle i had targeted 14deg +/- 5deg, since 14 was what i have in the idle regions of my ignition map, I see that you have dropped that down to 5deg and the swing is -5deg to 25deg, does that just give the idle control more leeway? I also saw the MAP lockout go up from 50kpa to 80kpa, i guess when the engine gets hot it pulls less vacuum?

    Really appreciate the help, I have learned a lot reading these forums :)

    Log

  16. RX7 Stalling when Hot

    in G4x

    Posted

    Hello,

    I have an 88 RX7 NA that I am in the middle of converting to Turbo, I am running the car with the Turbo intake for now so I can tune the NA regions:

    • 6 port NA block
    • Turbo II intake manifold with an air intake by the battery box
    • NA exhaust manifold without the heat shield (i think this is really heating up the intake...)
    • MonsoonX

    I have been trying to street tune it and for the most part it runs well once warmed up, but once the under hood temps start to pick up and my IATs reach 130F (54C), the car does not want to idle and will just stall out. Looking at the date, it seems as if the A/F mixture is going rich as things heat up, so maybe I need to adjust my Charge Air Temp Approx table some more. All other Fuel Corrections are turned off at the moment.

    Have a look around 25:08 where i am trying to keep the car alive at idle when the IATs are hot, you can see the stall. Any leads or help is greatly appreciated!

    Links:

  19. Charge Temp Approximation Table, FD RX7

    in G4+

    Posted

    hey @Pete_89t2, i know this is an old topic by now, but i was just curious if you were able to get some better numbers? I feel like on my RX-7 the exhaust and general heat held within the intake manifold are influencing the actual temperature of the air. I noticed that if my Charge Temp gets too warm, the car has trouble idling and will stall quite often, so I am looking for other ways to set this table properly.

    I have watched this Webinar: https://www.hpacademy.com/previous-webinars/075-charge-temperature-compensation-link-g4/

    Andre seems to take advantage of a dyno, which i don't have easy access to, so i was hoping to do this in my garage or with some logs from a drive

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