Explain knock readings?

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Explain knock readings?

This is a discussion on Explain knock readings? within the Veloster Turbo ECU Tuning and Data Logging forums, part of the Veloster Turbo Garage category; I've used a couple different scan tools, both have what I consider odd knock readings compared to what I'm used to seeing in other vehicles. ...

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    Explain knock readings?

    I've used a couple different scan tools, both have what I consider odd knock readings compared to what I'm used to seeing in other vehicles. I'm seeing knock, which is supposed to be in degrees, jump to 190 and back to 0, frequently on all cylinders, mostly during part throttle. I'm used to seeing varying single digit values, at high engine loads. These will decay back to 0 in a short amount of time. Anyone know what 190 means, or what units these are? Can't be degrees. Could this be knock counts rather than degrees of knock retard? Has anyone found these readings useful as is?


    Todd

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    It's in degrees. If it thinks knock is occurring it will be in the 180's and 190's with most tools. If using HP tuners it can read similar numbers to what you're used to.
    '15 Auto VT

    PB's with slips and video:

    60' ET 2.05
    1/8 ET 8.70
    1/8 MPH 85.68 MPH
    1/4 ET 13.421
    1/4 MPH 105.57 MPH

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    Quote Originally Posted by trdtoy View Post
    It's in degrees. If it thinks knock is occurring it will be in the 180's and 190's with most tools. If using HP tuners it can read similar numbers to what you're used to.
    Ok thanks. Would you happen to know how a 180 or 190 would correlate to a single digit value like HP tuners? Just trying to figure out if 190 is like 5 degrees of knock, or more, less? I don't know if 190 is bad or not. Wonder if this is a raw value that represents something else, but hasn't been converted.

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    The number you see is a raw value of when knock (K)occurs whereas the value you're used to seeing is knock retard(KR) or the amount of ignition timing pulled due to knock(K)
    '15 Auto VT

    PB's with slips and video:

    60' ET 2.05
    1/8 ET 8.70
    1/8 MPH 85.68 MPH
    1/4 ET 13.421
    1/4 MPH 105.57 MPH

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    Quote Originally Posted by trdtoy View Post
    The number you see is a raw value of when knock (K)occurs whereas the value you're used to seeing is knock retard(KR) or the amount of ignition timing pulled due to knock(K)
    trdtoy, just to clarify, you're saying that the knock that forcefed is seeing = k
    knock retard (typically a single digit value as mentioned by forcefed) = kr

    To summarize in an equation:
    k - kr ≤ 180°

    Agreed trdtoy?

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    Quote Originally Posted by BURN51D3 View Post
    trdtoy, just to clarify, you're saying that the knock that forcefed is seeing = k
    knock retard (typically a single digit value as mentioned by forcefed) = kr

    To summarize in an equation:
    k - kr ≤ 180°

    Agreed trdtoy?
    K is what he is seeing
    KR is what he is used to seeing
    0 simply means no knock

    Hard to get an equation as it only reports K not KR. All that matters is there is knock and thus KR and neither one is good when reported. Thing is sometimes it can be false reports and sometimes not.
    '15 Auto VT

    PB's with slips and video:

    60' ET 2.05
    1/8 ET 8.70
    1/8 MPH 85.68 MPH
    1/4 ET 13.421
    1/4 MPH 105.57 MPH

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    The device I'm using has 190 as the top of range, and I've never seen anything above this. Is this truly the max, because I see this all the time (with stock tune).

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    No this is not max per se as I've seen higher and lower numbers reported. What's more important is logging the car to see what it's doing.
    '15 Auto VT

    PB's with slips and video:

    60' ET 2.05
    1/8 ET 8.70
    1/8 MPH 85.68 MPH
    1/4 ET 13.421
    1/4 MPH 105.57 MPH

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