Knock sensor question

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anonymous.shyster
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Knock sensor question

Post by anonymous.shyster »

Quick question, is any knock sensor suitable for use with the Microsquirt? Or are they all a bit different so that I have to make sure that I'm getting the right type or style to suit the MS?

On a side, I'm a bit confused as to whether I need the 'knock sense". I don't think I do, as what I've read indicates that it was for older boards/code versions. I just want to make sure that if the engine does detonate, such as if I get a bad batch of fuel or balmy weather, that the engine is protected.
24c
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Re: Knock sensor question

Post by 24c »

anonymous.shyster wrote: I just want to make sure that if the engine does detonate, such as if I get a bad batch of fuel or balmy weather, that the engine is protected.
Weather should be fine, but I don't think there is a lot you can do about a bad batch of fuel without a knock sensor, other than read you the EGT as you drive (much like you do as you fly in light aircraft). OTOH, if you have a bad batch of fuel and say the engine is running weak, the O2 sensor (wideband) might see this and compensate with more poor grade fuel. :)
anonymous.shyster
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Re: Knock sensor question

Post by anonymous.shyster »

Ahh, not really an issue for me, as the MS is only controlling spark. Using four 40 mm CV Mikunis :D
anonymous.shyster
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Re: Knock sensor question

Post by anonymous.shyster »

Bumping this as I still haven't had my original question answered. Can I use any manufacture of knock sensor? Or does it need to be of some particular brand or type?
Matt Cramer
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Re: Knock sensor question

Post by Matt Cramer »

It's probably easiest to use a KnockSenseMS:

http://www.viatrack.ca
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anonymous.shyster
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Re: Knock sensor question

Post by anonymous.shyster »

I was of the impression that the Microsquirt would be able to take input directly from the sensor. Why do I need knocksense? Isn't the Microsquirt modular enough to take input from the sensor and retard timing accordingly?

I want to use a Toyota knock sensor as I need one that has a M12 sized thread and will be able to seal the coolant in with a copper gasket. Those sensors with a hole in them won't seal too well.
dontz125
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Re: Knock sensor question

Post by dontz125 »

The sensor is often particular to the engine (signal frequency is a function of the bore, or something like that IIRC), and the signal from the sensor must be filtered a magic'd to give something useful that the uS can understand. Hooking up a knock sensor to the uS is pretty much the same as directly hooking up a wideband O2 sensor - you won't gain anything, and you might break something in your uS.
anonymous.shyster
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Re: Knock sensor question

Post by anonymous.shyster »

Am I missing something? Can't the microsquirt be programmed to understand different inputs? Would it not be easier to find a conversion factor and let it know? Or is it just not modular enough?
Matt Cramer
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Re: Knock sensor question

Post by Matt Cramer »

anonymous.shyster wrote:I was of the impression that the Microsquirt would be able to take input directly from the sensor.
No, it can't.
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anonymous.shyster
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Re: Knock sensor question

Post by anonymous.shyster »

Why can't this stuff be done via software?
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