DIY Knock Monitor
Its easy, get a logger and go racing. Log each drag event. If timing is held or drops when the rpms are going up, then it is knock. Only exception is a peak tq it is NORMAL for the timing to dip a * or 2 and then continue up. This will happen when doing a long, one gear pull from low rpm. It will look like a "W" if you will. From higher rpms it should just go up.
Last edited by GraphiteMR; Oct 21, 2005 at 08:27 AM.
Originally Posted by gsujeff55
So, when logging timing while using a piggyback to tune with(logging with something like pocketlogger or similar) its nearly impossible to know if the timing values the motor is seeing are the timing values you have it set to see, or if the timing is something corrected by the ECU due to knock.
So, essentially, the only way to try to tune that way is on the dyno....where you can actually see dips in the power curve and try to find knock events. I really would like to be able to tune this thing on the street.
Could you get a true timing curve by logging a low boost pull with high octane....then upping the boost until you get to some knock and actually see timing pulled....just to make sure that the timing curve you actually saw is what you have it set to do?
that sounds kind of long-winded and confusing, do you guys get what im trying to say?
essentially, whats the best way to log a run where you will be guaranteed to see the timing you have the piggyback set to run?
-Jeff-
So, essentially, the only way to try to tune that way is on the dyno....where you can actually see dips in the power curve and try to find knock events. I really would like to be able to tune this thing on the street.
Could you get a true timing curve by logging a low boost pull with high octane....then upping the boost until you get to some knock and actually see timing pulled....just to make sure that the timing curve you actually saw is what you have it set to do?
that sounds kind of long-winded and confusing, do you guys get what im trying to say?
essentially, whats the best way to log a run where you will be guaranteed to see the timing you have the piggyback set to run?
-Jeff-
That's one of the problems...you really can't.
Your suggestion of doing a low boost pull on high octane is on the right track, but that will not work, either, because when you use the lower boost, the stock ECU will be using less conservative fuel and timing maps, along with being bumped backed even further by the piggyback. So, the only thing you will really accomplish with that method is seeing what your timing should be at that boost level.
Thinking about it a little here, I have a suggestion for you. I'm not sure what piggyback you use, but if it let's you reduce timing, then you could reduce timing across the board (or at least the higher load columns) by a certain number, like 5 degrees (or enough that you are abosultely sure you will not knock). Then, you can do a pull and log timing with a pocketlogger. Graph that data or timing vs RPM, and then add back in the 5 degrees to the timing that you took out. That graph will show you what your timing should be (assuming removing the 5 degrees prevented any knock). Then you can put your timing back to normal via your picggyback, do a pull and graph that RPM vs timing and compare the two. Any knock will be where the second line drops below the first (matching lines by RPM).
Eric
well, i use the xede. only problem with your suggestion is i don't acutally input timing values in degrees perse, it works in offsets of the stock CAS signal.
i wasn't aware that the ECU adjusts the timing based on the boost level....i thought the MAF scaling was essentially the same if you see what im sayin.
i thought the timing advance would be the same at 24psi as 20psi given there is no knock. i guess i was mistaken.
so, all else being equal(fuel, timing) dropping the boost won't give me an accurate 'no knock' timing reading....that i could use for a baseline for higher booost? that sucks.
HELP!
-Jeff-
i wasn't aware that the ECU adjusts the timing based on the boost level....i thought the MAF scaling was essentially the same if you see what im sayin.
i thought the timing advance would be the same at 24psi as 20psi given there is no knock. i guess i was mistaken.
so, all else being equal(fuel, timing) dropping the boost won't give me an accurate 'no knock' timing reading....that i could use for a baseline for higher booost? that sucks.
HELP!
-Jeff-
Originally Posted by gsujeff55
so, all else being equal(fuel, timing) dropping the boost won't give me an accurate 'no knock' timing reading....that i could use for a baseline for higher booost? that sucks.
HELP!
-Jeff-
HELP!
-Jeff-
There are timing maps that are different based on load and RPM, load being roughly proportional to boost. So, for example, the max timing at one load point may be 18 degrees and at the next higher load point (same RPM), it may be 15 degrees.
That is why timing settings for piggybacks, like the XEDE will not take any timing out, or possibly even have a negative offset. It is because the piggyback is knocking you back to a more aggressive (less load) timing/fuel map, where the timing is actual being increased from where the stock ECU would want it at that actual boost/load level.
Eric
Originally Posted by l2r99gst
Jeff,
That's one of the problems...you really can't.
Your suggestion of doing a low boost pull on high octane is on the right track, but that will not work, either, because when you use the lower boost, the stock ECU will be using less conservative fuel and timing maps, along with being bumped backed even further by the piggyback. So, the only thing you will really accomplish with that method is seeing what your timing should be at that boost level.
Thinking about it a little here, I have a suggestion for you. I'm not sure what piggyback you use, but if it let's you reduce timing, then you could reduce timing across the board (or at least the higher load columns) by a certain number, like 5 degrees (or enough that you are abosultely sure you will not knock). Then, you can do a pull and log timing with a pocketlogger. Graph that data or timing vs RPM, and then add back in the 5 degrees to the timing that you took out. That graph will show you what your timing should be (assuming removing the 5 degrees prevented any knock). Then you can put your timing back to normal via your picggyback, do a pull and graph that RPM vs timing and compare the two. Any knock will be where the second line drops below the first (matching lines by RPM).
Eric
That's one of the problems...you really can't.
Your suggestion of doing a low boost pull on high octane is on the right track, but that will not work, either, because when you use the lower boost, the stock ECU will be using less conservative fuel and timing maps, along with being bumped backed even further by the piggyback. So, the only thing you will really accomplish with that method is seeing what your timing should be at that boost level.
Thinking about it a little here, I have a suggestion for you. I'm not sure what piggyback you use, but if it let's you reduce timing, then you could reduce timing across the board (or at least the higher load columns) by a certain number, like 5 degrees (or enough that you are abosultely sure you will not knock). Then, you can do a pull and log timing with a pocketlogger. Graph that data or timing vs RPM, and then add back in the 5 degrees to the timing that you took out. That graph will show you what your timing should be (assuming removing the 5 degrees prevented any knock). Then you can put your timing back to normal via your picggyback, do a pull and graph that RPM vs timing and compare the two. Any knock will be where the second line drops below the first (matching lines by RPM).
Eric
run with associated knock log and timing retard every spike results in a ignition retard..as can be dissected.. after 3rd or 4th knock, the rate of ignition advance slows down top graph rpm, middle ignition timing, bottom knock voltage
2nd shows base ignition vs post adjustment advance.. 2nd one in hotter temperatures somemore..big chart redline base, greenline +2 offset
i hope this is what you're saying can't be done with piggybacks
don't want to be misunderstood.. i'll agree standalones are better.. but for lack of a good working standalone i have to make do with piggybacks.
Last edited by gunzo; Oct 21, 2005 at 07:55 AM.
Gunzo,
It's a little hard reading your graphs (edit, I posted before you had your second one up), but it looks like they are RPM, timing, and knock voltage, all vs time?
I'm not saying you can't log some of these things. I'm saying you don't know the exact timing that you should have and, therefore how much is being pulled. From your timing graph, you would have to look for downward spikes to see definite knock, but even areas of the graph that are flat or even going up can still be knock. It just depends on what point you are falling on the stock ECU timing map and whether or not the ECU is pulling any timing.
It's hard to explain, but that's OK. I was giving all of this info for Jeff. And I'm not saying that you shouldn't use piggybacks or even stand alones. I wish more people made the 'in-between' of the two like DSMLink, that uses the stock ECU, but enables you control of the parameters and full OBD-II logging, knock retard in degrees, etc.
I'm not here to debate that your piggyback isn't worth it. I'm just pointing out certain facts.
But, can you say that you know exactly what your timing should be at any RPM and look at your timing graph and say, without a doubt, it is knocking and how many degrees? I could with DSMLink. I could maybe show a little better with pictures later, but I'm just trying to explain the best I can.
Eric
It's a little hard reading your graphs (edit, I posted before you had your second one up), but it looks like they are RPM, timing, and knock voltage, all vs time?
I'm not saying you can't log some of these things. I'm saying you don't know the exact timing that you should have and, therefore how much is being pulled. From your timing graph, you would have to look for downward spikes to see definite knock, but even areas of the graph that are flat or even going up can still be knock. It just depends on what point you are falling on the stock ECU timing map and whether or not the ECU is pulling any timing.
It's hard to explain, but that's OK. I was giving all of this info for Jeff. And I'm not saying that you shouldn't use piggybacks or even stand alones. I wish more people made the 'in-between' of the two like DSMLink, that uses the stock ECU, but enables you control of the parameters and full OBD-II logging, knock retard in degrees, etc.
I'm not here to debate that your piggyback isn't worth it. I'm just pointing out certain facts.
But, can you say that you know exactly what your timing should be at any RPM and look at your timing graph and say, without a doubt, it is knocking and how many degrees? I could with DSMLink. I could maybe show a little better with pictures later, but I'm just trying to explain the best I can.
Eric
Last edited by l2r99gst; Oct 21, 2005 at 08:07 AM.
Its easy, get a logger and go racing. Log each drag event. If timing is held or drops when the rpms are going up, then it is knock. Only exception is a peak tq it is NORMAL for the timing to dip a * or 2 and then continue up. This will happen when doing a long, one gear pull from low rpm. It will look like a "W" if you will. From higher rpms it should just go up.
Originally Posted by l2r99gst
Gunzo,
It's a little hard reading your graphs (edit, I posted before you had your second one up), but it looks like they are RPM, timing, and knock voltage, all vs time?
It's a little hard reading your graphs (edit, I posted before you had your second one up), but it looks like they are RPM, timing, and knock voltage, all vs time?
Yes they are supposed to show you the above and I'm trying to say also .. I can see the base timing before I do anything .. the 2nd graph is supposed to show you the overlay between the stock ignition timing advance curve and the modified advance curve (which didn't come out nicely sorry)
I'm not saying you can't log some of these things. I'm saying you don't know the exact timing that you should have and, therefore how much is being pulled. From your timing graph, you would have to look for downward spikes to see definite knock, but even areas of the graph that are flat or even going up can still be knock. It just depends on what point you are falling on the stock ECU timing map and whether or not the ECU is pulling any timing.
I'm not here to debate that your piggyback isn't worth it. I'm just pointing out certain facts.
But, can you say that you know exactly what your timing should be at any RPM and look at your timing graph and say, without a doubt, it is knocking and how many degrees? I could with DSMLink. I could maybe show a little better with pictures later, but I'm just trying to explain the best I can.
Eric
But, can you say that you know exactly what your timing should be at any RPM and look at your timing graph and say, without a doubt, it is knocking and how many degrees? I could with DSMLink. I could maybe show a little better with pictures later, but I'm just trying to explain the best I can.
Eric
Well then .. gotta get the creator of DSMlink to start working on evos then .. hopefully they can port it across so I can use it too
Originally Posted by GraphiteMR
Once again, this is your answer. You don't need to know how much your ECU, retards, but if it retards at all.
My whole point was that you are still taking a best guess at it. That's all.
Eric
L2r99gst,
Good to see you over here as well as on DSMLink forums. I currently have the XEDE and boy do I miss the DSMLINK. I see Kevin is using the LINK but I just dont trust running a 10 year old ECU in my $30k car. I also dont trust the link is picking up knock like it should be on the EVO sensor. So far the best solution I came up with was to read timing. Kind of hard to do when actually racing but for tuning its not that difficult with some form of pocketlogger. I'm not on the bleeding edge so once tuned I dont really worry about it. I too am waiting for and EVO ECU EVOLINK solution.
When did you finally get your EVO?
Good to see you over here as well as on DSMLink forums. I currently have the XEDE and boy do I miss the DSMLINK. I see Kevin is using the LINK but I just dont trust running a 10 year old ECU in my $30k car. I also dont trust the link is picking up knock like it should be on the EVO sensor. So far the best solution I came up with was to read timing. Kind of hard to do when actually racing but for tuning its not that difficult with some form of pocketlogger. I'm not on the bleeding edge so once tuned I dont really worry about it. I too am waiting for and EVO ECU EVOLINK solution.
When did you finally get your EVO?
I just sold my Eclipse the other day. I have had my Evo for about a month now. I got the 05 with the 0% for 500 under invoice.
I finally put a CarPC in there and I so wish I had DSMLink running in it, but I sort of agree with you about running DSMLink. It's made for a DSM with a 95 ECU, not the EVO, although it will work. There are just a couple of nuiances that I don't want to deal with. And you point is good about the knock sensor, too. Testing needs to be done whether or not the knock sensors are compatible.
I'm shopping around for a decent piggyback, but I am having a hard time bringing myself to spend that much money for a piggyback.
Do you use the Pocketlogger to log timing? Can the XEDE read OBD-II data or is it just displaying the timing that it knows based on the your correction and the respective map the ECU will be on? The XEDE looks like a decent product, but the prices add up quickly and I would better off just buying another DSMLink. I'm also looking at the ECU+.
Nice to see you here, too.
Eric
I finally put a CarPC in there and I so wish I had DSMLink running in it, but I sort of agree with you about running DSMLink. It's made for a DSM with a 95 ECU, not the EVO, although it will work. There are just a couple of nuiances that I don't want to deal with. And you point is good about the knock sensor, too. Testing needs to be done whether or not the knock sensors are compatible.
I'm shopping around for a decent piggyback, but I am having a hard time bringing myself to spend that much money for a piggyback.
Do you use the Pocketlogger to log timing? Can the XEDE read OBD-II data or is it just displaying the timing that it knows based on the your correction and the respective map the ECU will be on? The XEDE looks like a decent product, but the prices add up quickly and I would better off just buying another DSMLink. I'm also looking at the ECU+.
Nice to see you here, too.
Eric
Originally Posted by gsujeff55
it is a 0-5v but i think its VERY weak.
we have been discussing this in the vishnu forum for a while, because i wanted to log knock sensor activity with my LM-1 wideband controller.
we have been discussing this in the vishnu forum for a while, because i wanted to log knock sensor activity with my LM-1 wideband controller.
-shiv, on isaac's computer
Alright Question :
Why are you guys trying to make a knock light ? Doesn't the knock sensor send the ECU into limp mode when it starts knocking ? Wouldn't that tell you for sure whether your engine is pre-igniting ? That along with the knocking sound ? I have never upped my compression ratio or used low octane gas so i don't know what you are trying to do . 
Why are you guys trying to make a knock light ? Doesn't the knock sensor send the ECU into limp mode when it starts knocking
? Wouldn't that tell you for sure whether your engine is pre-igniting ? That along with the knocking sound ? I have never upped my compression ratio or used low octane gas so i don't know what you are trying to do .
Originally Posted by isaac@vishnu
You can use our Knock Buffer to amp up the signal and then feed it into whatever monitoring device you want. Just don't tap into the knock signal until you do so since or the signal will deteriorate enough to make your car knock really bad
-shiv, on isaac's computer
-shiv, on isaac's computer
Originally Posted by Aux.
Alright Question :
Why are you guys trying to make a knock light ? Doesn't the knock sensor send the ECU into limp mode when it starts knocking ? Wouldn't that tell you for sure whether your engine is pre-igniting ? That along with the knocking sound ? I have never upped my compression ratio or used low octane gas so i don't know what you are trying to do .
Why are you guys trying to make a knock light ? Doesn't the knock sensor send the ECU into limp mode when it starts knocking
? Wouldn't that tell you for sure whether your engine is pre-igniting ? That along with the knocking sound ? I have never upped my compression ratio or used low octane gas so i don't know what you are trying to do .