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  1. 6 points
    This is the most pointless exercise ever, and i love it. I couldn't have even dreamed of anyone trying to measure knock with a jaycar multimeter. Also love your 20/20 hindsight knowledge. Everything anyone posts you 'already knew'. Good luck figuring it out!
  2. 5 points
    For f**k's sake Slap. You cannot measure frequency with voltages. You just cannot. It is time for you to let the big boys carry on and go play with your pathetic ideas quietly by yourself. Almost all of those ideas have no place in the real world anymore, as we have no need to bandaid shitty solutions to problems that can be fixed by proper selection and adjustment of the correct equipment.
  3. 4 points
    I've learnt heaps from this thread, please carry on. Slap is the the man.
  4. 4 points
  5. 4 points
    No, it cannot. From your posts it comes across like you have a LOT to learn, I'll try and give a bit of a concise enough ramble which if I get where you are at right and you are willing to take something on board it may help you think about things a bit differently and maybe learn something. So, think of knock sensors not as something measuring knock... but measuring the vibrations being transferred through whatever it is attached to. The sensor is effectively communicating the movement of those vibrations to the best of it's ability, it isn't giving a voltage representing the rate of the movements (aka frequency), but the strength and direction of those movements. If you had a sensor which was outputting a 1KHz square wave signal with a 1volt amplitude, and another sensor which was outputting a 1KHz square wave signal with a 2volt amplitude and tried to analyse that signal with a voltmeter you would not read the same voltage from those two sensors which are signalling the exact same frequency. Bearing that in mind, this pretty much explains why there is no set voltage where you are experiencing "knock". There are a few things which can influence what the signal from a knock sensor looks like - for starters: * Is it a resonant (more sensitive to a given frequency range) or a flat response sensor? * Where is the sensor located? * What is the resonant frequency of the engine being used? * What rpm is the engine operating at? * How noisy is the engine itself? You need signal processing of some sort if you hope to intelligently identify knock. You can probably do it with analog components but given the level of naivety you are indicating I could be forgiven for assuming you aren't going to be building custom circuits with effective utilisation of band pass filters etc to suit your given setup. There is a lot more data that comes from a knock sensor than just a threshold voltage which means knock, which means you really have to work to make reliable sense of it if you want automated detection of "stuff"- but you also can use them for a lot more too. This may give a bit of an indication of the kind of thing you can expect to see from a knock sensor, and what you can use the data for. In this case I was trying to identify the cause of a misfire on an car which pulling the plugs on to check was a non-trivial job, so I used windowing (split the signal from the knock sensor based off which cylinder was in it's combustion cycle so I align the noise with the busiest cylinder) and some signal filtering to even out the noise versus engine speed. Using that it became pretty clear which cylinder stopped firing when the car hit full boost.... check out the red line in the top graph. That's basically using less noise than "normal" to identify the lack of combustion, as opposed to using excessive noise to identify uncontrolled combustion. Analog tuning, what? PS, all of this is just trying to teach something with no rational thought process to react to a specific bunch of parameters you have set. It can't be guaranteed to always detect knock, and it can't be guaranteed that when it reacts that it is really knocking. It's just responding in prescribed way to a signal which meets some rules you've provided.
  6. 3 points
  7. 3 points
    No, E85 makes condensation. Because of the much higher hydrogen:carbon ratio of ethanol compared to 7-9 chain length hydrocarbons, it simply make a higher % of water vapour in the exhaust gases and therefore you get more of that condensing in the oil. Oil/sump temperature will be about the same regardless of 98/E85 fuel in use. It's the upper end of the engine that runs cooler. The bearings still make a lot of the heat that turns up in the oil, probably more on E85 if it's got more timing/boost/power. But the water is continuously being made. It should be safe to return it all to the sump, because the water should boil off again, but by the same token, if there's enough in there it will sink to the bottom of the sump, get priority pickup by the oil pump and f**k the bearings in short order. So, a large catch can and a very decent breather system that can pull off water vapour before it condenses and send it to be burnt are probably the wisest idea.
  8. 3 points
    Seriously dude you should stop giving advice
  9. 3 points
    Doing it wrong, 2kg of MB5+ Waygu Oyster Blade is already $120. By the time you add in truffle butter, artisan bread, and all the sides + the foie gras you're at $200+ already. I could easily spend $1k on feeding the kids.
  10. 2 points
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