EvoScan, Evo's, And Knock
Jul 20, 2006, 08:14 PM
#31
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93 FL gas.
I have a sway bar and short throw, which really are not important to this topic. I did just finish installing downpipe and cut out today so I will be doing more tuning this weekend with new setup.
Oh I have the boost pill removed for what its worth. I didn't have evo scan when I initialy started tunning I just went off wideband, but I am T'ed into knock sensor with Zeitronix also and during that tunning I would hardly ever see a spike in voltage.
I've adjusted the fuel tables, timing tables, mivec tables, stationary rev limiter, boost lmit, max wastegate duty, boost desired engine load, boost delay, and turbo boost error correction.
I have a sway bar and short throw, which really are not important to this topic. I did just finish installing downpipe and cut out today so I will be doing more tuning this weekend with new setup.
Oh I have the boost pill removed for what its worth. I didn't have evo scan when I initialy started tunning I just went off wideband, but I am T'ed into knock sensor with Zeitronix also and during that tunning I would hardly ever see a spike in voltage.
I've adjusted the fuel tables, timing tables, mivec tables, stationary rev limiter, boost lmit, max wastegate duty, boost desired engine load, boost delay, and turbo boost error correction.
Originally Posted by dudical26
What kind of gas?
Other then engine dampener, what mods do you have
what did you adjust when tuning
Did you have knock before you tuned it at all?
Other then engine dampener, what mods do you have
what did you adjust when tuning
Did you have knock before you tuned it at all?
Jul 21, 2006, 04:52 AM
#32
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Originally Posted by Ludikraut
^ What year was the Evo 8 that was logged?
l8r)
l8r)
I did a couple more pulls last night, again I am at work and can't post the logs untill later. Anyway, on my IX with the Intake and boost set at 20 PSI, running the e-flash but with the stock timing maps, I was getting knock from 1-3 over about half the log. For another run right after that, I was getting only a few knock counts, but the timing went down to -2 even with no knock in that area.
Overall very similiar behavior to my friends VIII
Jul 21, 2006, 08:09 AM
#34
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Alright, looks like the High Octane Timing map didn't change from the 2003 to 2005 stock Evo map (whew!). Looking at the Evo VIII logs, it looks like maybe 1 degree of timing was pulled at times. Even the log that shows -1 degree of timing actually stayed in the high octane timing map ... the car just went to a higher load cell during that run. Take a look at the following maps that illustrate the 20.5 PSI runs.
First 20.5 PSI run (black dots = initial gear, red dots = next gear):
Second 20.5 PSI run:
Now if you use Eric's formula for calculating the Load (%), you get:
So it looks like perhaps 1 degree of timing was pulled on both of the 20.5 PSI runs near 4000 RPM. I didn't calculate the remainder of the logs, but hopefully this points you in the right direction.
l8r)
First 20.5 PSI run (black dots = initial gear, red dots = next gear):
Second 20.5 PSI run:
Now if you use Eric's formula for calculating the Load (%), you get:
So it looks like perhaps 1 degree of timing was pulled on both of the 20.5 PSI runs near 4000 RPM. I didn't calculate the remainder of the logs, but hopefully this points you in the right direction.
l8r)
Jul 21, 2006, 09:34 AM
#38
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nj, that's pretty close, although you may want to plot the timing for each row in the middle, instead of on the bottom - i.e. at 3500 RPM your log shows 3*, so put the dot in the middle of the 3500 RPM row, between the 5* and 2* cell (closer to the 2).
I generally only put the easily plotted RPM figures onto the timing map, which would be every 250 or every 500 RPM (depending on the detail of the log). The 500s go into the middle of each row, the 250s go onto the dividing lines between each row.
Once you have the general shape of the timing path, you can get really **** and figure out where it "should" have been vs. where it ended up by using Eric's formula. Someone else came up with a formula that allegedly was more accurate, but I couldn't get it to compute.
HTH
l8r)
I generally only put the easily plotted RPM figures onto the timing map, which would be every 250 or every 500 RPM (depending on the detail of the log). The 500s go into the middle of each row, the 250s go onto the dividing lines between each row.
Once you have the general shape of the timing path, you can get really **** and figure out where it "should" have been vs. where it ended up by using Eric's formula. Someone else came up with a formula that allegedly was more accurate, but I couldn't get it to compute.
HTH
l8r)
Jul 21, 2006, 10:41 AM
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Ludikrat, Thank you that was helpfull. I will post my more recent logs from my IX when I get home. Hopefully you can help to shed some light on these as well.
Thanks
Thanks
Jul 21, 2006, 11:51 AM
#40
Just keep in mind that my formula is not the exact forumla. You may have to mess around with the constant to make it accurate it for you.
Once EvoScan starts logging mass airflow, I know that I can come up with a much better forumla, as the load is related to the mass airflow per revolution.
The other forumla that was mentioned tried to take the baro and temperature into account....that's why I say that you may have to slightly adjust the constant that I gave depening on your setup and conditions at the time of logging.
But, once EvoScan can log mass airflow, like lb/min or g/s, that number is already calculated by the ECU using the temp and baro, so I think I will be able to get a pretty accurate load formula for everyone. Then we can settle once and for all how much timing is being pulled due to knock.
Eric
Once EvoScan starts logging mass airflow, I know that I can come up with a much better forumla, as the load is related to the mass airflow per revolution.
The other forumla that was mentioned tried to take the baro and temperature into account....that's why I say that you may have to slightly adjust the constant that I gave depening on your setup and conditions at the time of logging.
But, once EvoScan can log mass airflow, like lb/min or g/s, that number is already calculated by the ECU using the temp and baro, so I think I will be able to get a pretty accurate load formula for everyone. Then we can settle once and for all how much timing is being pulled due to knock.
Eric
Jul 23, 2006, 04:49 PM
#42
Look what I found while reading this article
http://www.innovatemotorsports.com/r...ecu-basics.php
The second common and important feedback sensor is a little microphone attached to the engine block that can sense “knocking” or detonation from the cylinders, allowing the computer to adjust the timing backward (later) to prevent damage to the pistons. A few knocks per 100 cycles will be OK. More is bad. Note that there can be problems associated with this sensor: the Mitsubishi 4G63 engines especially in Galant VR4s and Talons can be afflicted with a “phantom knock” even when the engine is running properly but goes into limp mode anyway, sapping power. Basically the microphone is picking up noise from somewhere else in the engine and sending it to the computer as a knock; many Mitsu people find that the valve lifters are the source of the noise. Similarly, in a rally car we have constant barrage of noise from rocks on the chassis and this can be picked up. As a result, I don’t have a knock sensor.
It seems that our 4g63 engine is well known for giving pahntom knock. And notice what the guy says "A few knocks per 100 cycles will be OK."
And on top of that the guy owns an EVO and tunes it himself
http://www.innovatemotorsports.com/r...ecu-basics.php
The second common and important feedback sensor is a little microphone attached to the engine block that can sense “knocking” or detonation from the cylinders, allowing the computer to adjust the timing backward (later) to prevent damage to the pistons. A few knocks per 100 cycles will be OK. More is bad. Note that there can be problems associated with this sensor: the Mitsubishi 4G63 engines especially in Galant VR4s and Talons can be afflicted with a “phantom knock” even when the engine is running properly but goes into limp mode anyway, sapping power. Basically the microphone is picking up noise from somewhere else in the engine and sending it to the computer as a knock; many Mitsu people find that the valve lifters are the source of the noise. Similarly, in a rally car we have constant barrage of noise from rocks on the chassis and this can be picked up. As a result, I don’t have a knock sensor.
It seems that our 4g63 engine is well known for giving pahntom knock. And notice what the guy says "A few knocks per 100 cycles will be OK."
And on top of that the guy owns an EVO and tunes it himself
Last edited by nj1266; Jul 23, 2006 at 04:57 PM.
Jul 23, 2006, 05:56 PM
#43
Originally Posted by nj1266
Look what I found while reading this article
http://www.innovatemotorsports.com/r...ecu-basics.php
The second common and important feedback sensor is a little microphone attached to the engine block that can sense “knocking” or detonation from the cylinders, allowing the computer to adjust the timing backward (later) to prevent damage to the pistons. A few knocks per 100 cycles will be OK. More is bad. Note that there can be problems associated with this sensor: the Mitsubishi 4G63 engines especially in Galant VR4s and Talons can be afflicted with a “phantom knock” even when the engine is running properly but goes into limp mode anyway, sapping power. Basically the microphone is picking up noise from somewhere else in the engine and sending it to the computer as a knock; many Mitsu people find that the valve lifters are the source of the noise. Similarly, in a rally car we have constant barrage of noise from rocks on the chassis and this can be picked up. As a result, I don’t have a knock sensor.
It seems that our 4g63 engine is well known for giving pahntom knock. And notice what the guy says "A few knocks per 100 cycles will be OK."
And on top of that the guy owns an EVO and tunes it himself
http://www.innovatemotorsports.com/r...ecu-basics.php
The second common and important feedback sensor is a little microphone attached to the engine block that can sense “knocking” or detonation from the cylinders, allowing the computer to adjust the timing backward (later) to prevent damage to the pistons. A few knocks per 100 cycles will be OK. More is bad. Note that there can be problems associated with this sensor: the Mitsubishi 4G63 engines especially in Galant VR4s and Talons can be afflicted with a “phantom knock” even when the engine is running properly but goes into limp mode anyway, sapping power. Basically the microphone is picking up noise from somewhere else in the engine and sending it to the computer as a knock; many Mitsu people find that the valve lifters are the source of the noise. Similarly, in a rally car we have constant barrage of noise from rocks on the chassis and this can be picked up. As a result, I don’t have a knock sensor.
It seems that our 4g63 engine is well known for giving pahntom knock. And notice what the guy says "A few knocks per 100 cycles will be OK."
And on top of that the guy owns an EVO and tunes it himself
But, be careful. Don't just assume that a few knock counts are phantom knock. Even 1 count is bad if it is real knock. The amount of force on the bearings when knock occurs can eventually cause engine failure.
It's just me, but I will always tune on the safe side, for 0 knock.
Eric
Jul 24, 2006, 02:40 PM
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Originally Posted by jcsbanks
I'm fairly relaxed about the log behaviour because I have listened to the engine with my own ears (through det cans) and know that it doesn't knock except occasionally on lift off (most of which I've also sorted) and it performs very well. I get sporadic low grade counts of 1s which I think are meaningless. 2s and 3s show I'm running it a bit "sparklier" as I call it. When I've seen a 4 occasionally (especially as a spike) on logs I have also found that there has been detonation and the timing seems to get pulled, but I then tune this out.
So I'm "cooperating" with the OEM knock control system and it seems to work. Knock is a sporadic thing and I'm pleased that the system is there in the background. I'm not getting hung up over a degree or so here and there and generally I find the system behaves appropriately. I'm cooperating because if I put more timing in the ECU seems to pull most of it out again. Even with methanol in the tank (with safe lambda) and no extra timing it will still do the odd 1 or 2 during spool up even with -1 or -2 timing. It hauls hard and doesn't knock so I don't mind.
Significant knock is probably being prevented by the OEM system doing its trimming work. Since there are tables in the ECU that reveal it can pull out substantial spark timing before the next spark, it may be that the brief noises are too short for me to hear even through det cans.
So I'm "cooperating" with the OEM knock control system and it seems to work. Knock is a sporadic thing and I'm pleased that the system is there in the background. I'm not getting hung up over a degree or so here and there and generally I find the system behaves appropriately. I'm cooperating because if I put more timing in the ECU seems to pull most of it out again. Even with methanol in the tank (with safe lambda) and no extra timing it will still do the odd 1 or 2 during spool up even with -1 or -2 timing. It hauls hard and doesn't knock so I don't mind.
Significant knock is probably being prevented by the OEM system doing its trimming work. Since there are tables in the ECU that reveal it can pull out substantial spark timing before the next spark, it may be that the brief noises are too short for me to hear even through det cans.
Exactly! Trust that stock knock system. Don't alter the knock tables. It works as advertised. Sometimes you do get false knock. We call it "partial throttle" knock in dsm's. It's generally not real and we've programmed the stock ecu to ignore knock till a certian load value. When these cars get 5-6 years older, this "phantom knock" will become an issue. Right now just keep things tight in the engine bay with nothing rubbing and trust that sensor. Its the rider that keeps the reighns in control and saves the day more often than it causes trouble.
Jul 24, 2006, 02:55 PM
#45
This is assuming the car is unmodified with stock pistons, soft motor mounts and stock suspension. Once you start modifying and stiffening up the car these vibrations begin to be picked up by the knock sensor. I am having to replace a stiff rear motor mount with a stock one just for this reason. 35 counts of knock at 17% TPS cruising. I watch as the ECU pulls out 30* of timing all the way to -10* and watch the EGTs climb.
At some point you have to address the filters or car's setup.
At some point you have to address the filters or car's setup.