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Slap, the problem is what you have said doesn't make sense. How are you getting these knock voltage readings?

The ecu doesn't adjust some kind of voltage to tune its own knock sensitivity. If you want some technical reading check out the nistune forum. That is where to find out how the skyline ecu works 

 

 

  • Like 2
12 minutes ago, Slap said:

Thread ruined. Locking the door on this one for me. Maybe someone that is interested in how the ecu works (not just gets tuned) will make a thread where I can have discussion without a pack of priests raping me over the sacrilege of my non beliefs in there bible.

 

Ha! No, you don't want a discussion on how the ECU works.  What you want is to either have us slavishly agree with your wrong opinion on how it works, or spoon feed you with 3rd party references to demonstrate why what we have said is correct.  It's really not up to us to prove to you why you are wrong.  You can ignore a strong concensus of people who have actually opened up and performed surgery on Nissan ECUs is you want.  People who have replaced internal components, swapped processors and EEPROMs out for Nistune boards, soldered programmers in, fault found any number of reasons why a given ECU wasn't working, etc etc.

Or you can be a dick.  We actually don't care.

  • Like 3
Slap, type less statements ask more questions.  I have a Billy Madison quote here but I'll just say I award you no points, and may God have mercy on your soul. 

 

Ok. You put that well and I love that movie. 

Wasn't gonna reply again to this thread.

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WHY WHEN A VOLTAGE READING IS TAKEN FROM EACH KNOCK SENSOR WIRE NEAR THE ECU DOES THE READING STAY AT 2.4 V AND OCCASIONLY DROP TO 2.3 V... BUT WHEN I USE MY PLEX M300 te TO CHANGE OVER TO E85 IT WILL GRADUALY GO DOWN AND STAY AT 2.1 V...

THEN CHANGE BACK SLOWLY WHEN RUNNING ON 98 AGAIN?

***************************************

ALSO IF CAS TIMING IS 15-17°....HOW MUCH TIMiNG IS ADDED AT IDLE FROM THE ECU?

***************************************

HOW MANY VOLTS DOES THE ACTUAL NOISE OF KNOCK PRODUCE?

****************************************

HOW MANY VOLTS IS THE ENGINE NOISE FREQUENCY SET TO AS A FILTER? 2.4V?

*****************************************

 

Im not yelling just making the question stand out.

 

If you want to smack my bum go away.

 

 

 

 

Ummm see below of how a 'knock sensor' works.

I took this reading on an actual engine block (in the right location) to determine the natural frequency which equated 100% to the factory OEM SAE paper listing the same for the given engine type. Also shown for your benefit is the 'voltage' typically seen on an acceleration sensor or microphone which is what some call it.

Not sure if this input is going to help the OP though? :)

yohomeO.jpg

  • Like 1
Ummm see below of how a 'knock sensor' works.
I took this reading on an actual engine block (in the right location) to determine the natural frequency which equated 100% to the factory OEM SAE paper listing the same for the given engine type. Also shown for your benefit is the 'voltage' typically seen on an acceleration sensor or microphone which is what some call it.
Not sure if this input is going to help the OP though? :)
yohomeO.thumb.jpg.6b8e80928c1430de1f015b85ef5486c2.jpg
Omg thank you for a decent response.

I can see that the knock noise produces what I think is about .36v.

Was the reading from a consult or is that direct voltage from the wires (at the block?) as I'm not sure a consult will show engine noise frequency?

I am under the belief that the readings I get from the ecu wires that are 2.4v and lower, to be the engine noise voltage and that the ecu is listening for spikes of *(.36).
So using the 2.4v as a baseline for the frequency to work from.

Also I believe as I've seen and in the past read that the base line frequency will lower until the ecu can hear the frequency if the knock frequency (*.36) is weak meaning it's a lower voltage/frequency from less knock.

Note* i have never used a dyno. I have witnessed this at idle wasting lots of fuel letting the ecu set the best idle after fuel switching.

Do people know what I mean when I talk about analogue tuning?

(Using mechanical and electrical modification to achieve a better tune)

And of course this goes best with a digital tune and dyno runs.

[emoji846][emoji854] discussion finally.

They way I talk is different to other kunts :) but the voltage and associated threshold is usually listed as a percentage of saturation, which is correlated to the voltage out of the unit. When you test it and smash the kunt *engine-NOT the sensor!* with a hammer :) you can easily get over the voltage you mention. This then is where you set your gain value to being the knock sensor into a workable range on your specific ECU and then to differentiate the normal noise of the engine (proportional to BMEP and rpm)......... it gets complex but that is it, you tailor find the natural frequency of the system (not by internet calculators or multiple frequency tests like some ECU makers suggest!) but rather you test it on the engine (not hard to do as I am a dumb kunt and I worked it out myself). Then adjust for normal operation and I have not found an engine yet that cant be set up correctly without the need for any third party knock devices, assuming you know what you are doing.

Some engines (rotaries which I know better than most, especially as we run the knock limited all the time) will not tolerate much detonation so you have to know what you are doing. 4cyl engines which are 'noisy' are hard to set up right.

Using generic wide range knock sensors I don't recommend, I wont divulge why (as too many stalkers read everything I put up lol) but I will say that the right tool for the job is usually the best practice :) Final note is if you are using 'audible knock tools as validation' then you are a rookie, don't hand out advice to others please LOL I talk more about that here below.

http://www.aquamist.co.uk/forum2/vbulletin/showthread.php?t=1590&page=42

Senior Member
 
Join Date: Oct 2003
Location: Utopia
Posts: 429
 
ExclamationRe: RICESP Water Injected RX7

It's all about knock control, running the engine to its limit (even a 100% standard delivered engine) when I was proving this system.

Water Injection, and a real not paper/internetz professional control box, and a person with a brain are all that is required. Seems simple but these days ironically it's harder than ever (too much wrong advice from nobodies on everything from shit electronics choices onwards) go figure!

FYI human reaction time to audio stimulus is around 0.170 seconds, given below example of 0.0066 seconds per cycle event, this means the rotary engine will knock>detonate at least 25 times before you lift your foot off the accelerator LOL smile.gif "retarded" in every sense of the word, love the internetz education handed out by educatorz/trainerz/tutorz LOLZ smile.gif

Anyway onto real qualified information:
It's easy with the right electronics/hardware/software, to not only see what is happening, but also manage it (100% stock standard 'fragile' rotary engine) running it to its knock limits all of the time in an active manner, and letting the ECU manage the spark timing. Counter to the 'shit advice' that proliferates the internetz blogs etc, this is the preferred way, counter to their claims of doom and gloom, ironically its opposite (wow surprise!) if you are NOT running a Life Racing ECU (set up correctly) you will have zero hope of relying on your new found 'pay to play' derived 'knowledge' since the nature of knock by the many variables that cause it means you have to run so far away from peak performance that you will either melt your turbine, have poor specific power, poorer fuel specific fuel consumption, and far less durability all rolled into one! p.s Would love to put up a jizzillion pages of information, but learned long ago too many copy it so as its all current technology stuff reserved only for the smart/loyal ones smile.gif who know how to tell FACT from FICTION smile.gif

Hmmmm, Really need to put up another graph of flat shift full throttle cuts example, with anti lag, and Traction Control!!! which some seem to get LINK'd to the wrong advice again LOL.........
49jhmJg.jpg
__________________
  • Like 1
3 hours ago, Slap said:

I am under the belief that the readings I get from the ecu wires that are 2.4v and lower, to be the engine noise voltage and that the ecu is listening for spikes of *(.36).
So using the 2.4v as a baseline for the frequency to work from.

No.

Rice's pictured waveform is the AC audio signal produced by a SINGLE ping event (or a hammer strike if that's the way he generated the noise).

You cannot make the measurements that you have with a simple voltmeter because it is the wrong tool and showing you numbers that have no meaning.

Analogue tuning by signal bending is dead.  It is not the 1990s any more.

  • Like 3
No.
Rice's pictured waveform is the AC audio signal produced by a SINGLE ping event (or a hammer strike if that's the way he generated the noise).
You cannot make the measurements that you have with a simple voltmeter because it is the wrong tool and showing you numbers that have no meaning.
Analogue tuning by signal bending is dead.  It is not the 1990s any more.
I think that you saying no. And saying anoulouge tuning bending signals shows you don't understand.

The frequency can be measured by voltage.

What are the voltages showing in the video if not engine noise voltage?

Why did they go lower on e85

Signal bending with the safc is still a digital way to control the signal. Even if it's not proper and stop going on about the safc.
I use it as an fcd and a 2 step and it is map hacked so it takes throttle position from a map sensor meaning it's boost referenced.

I can see his picture and I can see it does 0.36v as knock noise.
The wave form is still a voltage.
How else can the ecu distinguish the difference between engine noise and knock noise.
They don't have ears. It uses a voltage frequency that can be output in audio similar to how it was input from audio.

Here are some examples of anolouge tuning.

 

Cam gears . If I advance the exahust cam a few degrees it throws the cas.

 

Cas correction or adjustment.

 

Unmetered air inlet bypass - to extend maf.

 

Resistors in place of sensors.

 

I have even experimented with extra injectors as auxiliary feed on boost control switches and as sequential injectors too.

But with out better control are useless.

 

A pod

A zorst

A turbo

Bleed valve

Fark even the idle valve is anolouge.

 

These don't contain an electronic control module or display to function.

 

 

 

 

 

 

 

 

 

 

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.

  • Like 4
  • Haha 1

My offer stands, I can supply you with a Nistune board, installation by Matt at Nistune himself, have the ECU bench tested and sent back.

Also it supports full flex, launch control, boost control.

 

Omg I don't want to buy your nistune as i could easy get 1 cheap.
I have a wolf I'm selling as it's cheaper to make my 6lt the power house and just toy with the rice bubbles as they are my favs.

This is discussion and the same 3 fools just wanting to shut me down.

What is voltage? (A frequency)

Look past your pc boys theres components and mods that don't get controled by that.

Also people still use this technology its just people like you expect others to sell a kidney to buy an ecu and get it on a dyno.

My questions still stand if any one can answer them.

Really now? I am a dealer, so I'm not sure how you can get it cheaper new.
Second hand.



I found this article. I havent finished reading yet.
Arhg it wont let me upload the pdf.
I added a pic and also a pic of the pdf searched on google. "Wellsve.com"

It does state that the sensor sends the audio signal as a voltage to the ecu.
I understand that my setup doesnt show the knock lvl.

Im sure It is the voltage the sensors run at as a baseline.
Screenshot_20190303-151110_Drive.jpegScreenshot_20190303-151326_Google.jpeg
2 hours ago, Slap said:


The frequency can be measured by voltage.
 

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? :P

No photo description available.

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.

Edited by Lithium
  • Like 4

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