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      07-15-2009, 09:16 PM   #23
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      07-15-2009, 09:17 PM   #24
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Whitesled are you saying that with the procede the engine is adding timing even at partial throttle? or there's a possibility that it is?
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      07-15-2009, 09:22 PM   #25
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Quote:
Originally Posted by roozie2001 View Post
Whitesled are you saying that with the procede the engine is adding timing even at partial throttle? or there's a possibility that it is?
Looks like Whitesled is banned for being naughty so I don't think he's saying much. But yes, for the last several months the PROcede has been adding 2-3 degrees of timing during light cruise conditions. This improves fuel economy by 2-5mpg depending on cruise RPM.

Shiv
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      07-15-2009, 09:26 PM   #26
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Interesting and looking forward, time willing, to performing my own tests.

I would like to see counter data instead of assumptions. But I doubt I will see it in my life time.
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      07-15-2009, 09:31 PM   #27
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Quote:
Originally Posted by cincy335i View Post
Great info...thanks for clarifying and taking the time, money and energy to conduct these tests and explain to us in laymens's terms. Looking forward to the next batch of maps, firmware and custon tune documentation.

So do you think that with running the midwest best 94 octane that we could actually lower the timing advance % to say around 50-70% and avoid knock (making more power)? it is just a question to if you think that would work, knowing that it would be best to leave it at 100%, please don't roast me over it. LOL Anyways thanks again...great work!

So Shiv, do you think it is possible or should I say semi-safe to avoid knock at these percentages (ignition correction %) running 94 octane? Thanks, keep up the great work.
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      07-15-2009, 09:32 PM   #28
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Quote:
Originally Posted by cincy335i View Post
So Shiv, do you think it is possible or should I say semi-safe to avoid knock at these percentages (timing %) running 94 octane? Thanks, keep up the great work.
Stay at the default for now. Once i post up the custom tuning guide, you can dial in more power if you choose.

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      07-15-2009, 09:35 PM   #29
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Great...thanks, looking forward to the new maps and tune documentation.

So any teasers or tidbits surrounding the boost display in dash with other in dash fun info...coming soon?

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      07-15-2009, 09:47 PM   #30
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I hope I'm invited to participate?

The biggest issue here is finding a reliable method to determine knock retard is taking place. Prior to the BT cable and being able to readout and study the actual ECU timing tables from the BIN we used to think sudden drops in total timing advance equated to knock retard. The more severe the drop the worse the knock retard.

Since we've learned that this isn't the case. The "knock response" system is indexed by total timing advance, and broken in to long and short term trims. The further down either timing scale you are, the more aggressively the ECU reduces timing as a function of knock sensor feedback. So in a non-CPS offsetting environment the entire system is more sensitive to pulling timing based on feedback. This is a very good thing for safety.

To make a long story short, determing knock retard is taking place and to what degree requires some sophistication. Monitoring total timing advance is not sufficient.

Mike
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      07-15-2009, 10:08 PM   #31
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Quote:
Originally Posted by Mike@N54Tuning.com View Post
I hope I'm invited to participate?

The biggest issue here is finding a reliable method to determine knock retard is taking place. Prior to the BT cable and being able to readout and study the actual ECU timing tables from the BIN we used to think sudden drops in total timing advance equated to knock retard. The more severe the drop the worse the knock retard.

Since we've learned that this isn't the case. The "knock response" system is indexed by total timing advance, and broken in to long and short term trims. The further down either timing scale you are, the more aggressively the ECU reduces timing as a function of knock sensor feedback. So in a non-CPS offsetting environment the entire system is more sensitive to pulling timing based on feedback. This is a very good thing for safety.

To make a long story short, determing knock retard is taking place and to what degree requires some sophistication. Monitoring total timing advance is not sufficient.

Mike
Ok Mike.

Shiv
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      07-15-2009, 10:12 PM   #32
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Quote:
Originally Posted by Mike@N54Tuning.com View Post
I hope I'm invited to participate?

The biggest issue here is finding a reliable method to determine knock retard is taking place. Prior to the BT cable and being able to readout and study the actual ECU timing tables from the BIN we used to think sudden drops in total timing advance equated to knock retard. The more severe the drop the worse the knock retard.

Since we've learned that this isn't the case. The "knock response" system is indexed by total timing advance, and broken in to long and short term trims. The further down either timing scale you are, the more aggressively the ECU reduces timing as a function of knock sensor feedback. So in a non-CPS offsetting environment the entire system is more sensitive to pulling timing based on feedback. This is a very good thing for safety.

To make a long story short, determing knock retard is taking place and to what degree requires some sophistication. Monitoring total timing advance is not sufficient.

Mike
Not sure exactly what you're saying. Does this have anything to do with any particular tuner's proprietary system of knock control?
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      07-15-2009, 11:27 PM   #33
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Quote:
Originally Posted by Mike@N54Tuning.com View Post
I hope I'm invited to participate?

The biggest issue here is finding a reliable method to determine knock retard is taking place. Prior to the BT cable and being able to readout and study the actual ECU timing tables from the BIN we used to think sudden drops in total timing advance equated to knock retard. The more severe the drop the worse the knock retard.

Since we've learned that this isn't the case. The "knock response" system is indexed by total timing advance, and broken in to long and short term trims. The further down either timing scale you are, the more aggressively the ECU reduces timing as a function of knock sensor feedback. So in a non-CPS offsetting environment the entire system is more sensitive to pulling timing based on feedback. This is a very good thing for safety.

To make a long story short, determing knock retard is taking place and to what degree requires some sophistication. Monitoring total timing advance is not sufficient.

Mike
Can you please explain more in depth I follow what your saying about short and long term trims but can you provide more depth to what your saying.
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      07-15-2009, 11:38 PM   #34
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Quote:
Originally Posted by Mike@N54Tuning.com View Post
I hope I'm invited to participate?

The biggest issue here is finding a reliable method to determine knock retard is taking place. Prior to the BT cable and being able to readout and study the actual ECU timing tables from the BIN we used to think sudden drops in total timing advance equated to knock retard. The more severe the drop the worse the knock retard.

Since we've learned that this isn't the case. The "knock response" system is indexed by total timing advance, and broken in to long and short term trims. The further down either timing scale you are, the more aggressively the ECU reduces timing as a function of knock sensor feedback. So in a non-CPS offsetting environment the entire system is more sensitive to pulling timing based on feedback. This is a very good thing for safety.

To make a long story short, determing knock retard is taking place and to what degree requires some sophistication. Monitoring total timing advance is not sufficient.

Mike
Would you happen to have any data to support what you are saying?
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      07-16-2009, 12:23 AM   #35
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Quote:
Originally Posted by shiv@vishnu View Post
Ok Mike.

Shiv
Thanks for letting me participate. We can talk about "knock" and timing advance values in a bit, but first I have a few questions about the data posted.

From Test 1:

Quote:
Note that boost is at a stock-like 6-10psi. There is no Ignition Correction. Hence, DME timing equals Actual Timing. Notice how the timing curve is nice and linear. Reaching 9.5 degrees by 6000rpm and 13.5 deg by 7000rpm. This represents the maximum timing values the factory DME will target for this IAT, oil temp, water temp, etc,. conditions. In other words, even on 100oct race fuel, the logged timing values will not increase.
Also note that the stock timing at 5000rpm, peak boost, is 9 degrees.

From Test 2:

Quote:
Now the PROcede is active and boost is at boost is at 14-16psi depending on RPM. As one would expect, the PROcede responds by actively inducing 2-3.5 degrees of ignition retard (negative correction). Now Actual Timing is 2-3.5 degrees lower than it was in Test 1 (stock tune). However, DME Timing is still the same (9.5 degrees by 6000rpm, 13.5 deg by 7000rpm) and still its its maximum limit. And as far as the DME can see, the engine is running normally with the expected amount of ignition advance.
Now note that the timing at 5000rpm is down to 5 degrees, or approximately half of the stock map value. The ECU is not running at the maxed out stock values, yet you state it is. Can you explain the discrepancy?

Mike
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      07-16-2009, 12:26 AM   #36
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Quote:
Originally Posted by got psi View Post
Please elaborate as to what you're getting at. I'm not following here...
It simply means that using the single total timing advance parameter as a gauge for knock is very inaccurate, for many reasons. And yes, I have data to back that up. I am just getting back from a 4 week trip and need to get caught up, but will be happy to share the data as time permits. To really understand knock retard you need to study the knock sensor signals directly, and the "status_knocking" flag in the ECU. I have found it to be a very accurate indicator of actual knock as common sense would dictate.

Mike
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      07-16-2009, 12:28 AM   #37
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Quote:
Originally Posted by usc335 View Post
Would you happen to have any data to support what you are saying?
Hey, stop bugging the guy!
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      07-16-2009, 01:22 AM   #38
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Quote:
Originally Posted by Mike@N54Tuning.com View Post
Thanks for letting me participate. We can talk about "knock" and timing advance values in a bit, but first I have a few questions about the data posted.

From Test 1:
Also note that the stock timing at 5000rpm, peak boost, is 9 degrees.

From Test 2:
Now note that the timing at 5000rpm is down to 5 degrees, or approximately half of the stock map value. The ECU is not running at the maxed out stock values, yet you state it is. Can you explain the discrepancy?

Mike
Sure thing Mike. One of the biggest contributors of the initial timing target is Intake Air Temp. The higher it is, the lower the initial timing target. In the higher boost runs, initial IATs were in the 119-126F deg range. This is because I did several back to back adaptation runs before the logged run. In the stock tune run, initial IAT was under 100F, rising to only 105F (it's really hard to equal IATs when you are only running 6-9psi of boost). It's as if the DME is testing the waters first, and only after that, does it start to roll in the desired ignition advance. And the rate of additive advance seems to depend on a number of things including the acceleration of the engine. And judging by the time stamps, you'll notice that the tuned runs are accelerating a lot quicker than the stock tune run.

But yes, in that particular case, there is probably 1-2 degrees of reactive DME retard in the 5000-5500rpm as suggested by slightly more ign. advance shown in Test 4 (with 200% Ign Correction). Just not the 4 degrees that you suggest.

However, the real point of this exercise was to illustrate the effect the PROcede's CAS offsetting feature had on Actual Ignition Advance. More than once, you/Terry have stated that the DME will run whatever it wants to run, regardless of CAS offsetting. You've even went so far as to say that CAS offsetting doesn't work at all and that the DME will just "learn" around it. I never thought I needed to take the time to prove that such claims were unfounded. But after hearing several people accept this claim as fact, I took the time to prove otherwise and post are the results. And these results can soon be replicated by hundreds of Rev.2 users out there.

Cheers,
Shiv
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      07-16-2009, 01:25 AM   #39
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Quote:
Originally Posted by Mike@N54Tuning.com View Post
It simply means that using the single total timing advance parameter as a gauge for knock is very inaccurate, for many reasons. And yes, I have data to back that up. I am just getting back from a 4 week trip and need to get caught up, but will be happy to share the data as time permits. To really understand knock retard you need to study the knock sensor signals directly, and the "status_knocking" flag in the ECU. I have found it to be a very accurate indicator of actual knock as common sense would dictate.

Mike
Please explain. And please post this data you are referring to. Hopefully it's not proprietary. Do you know when time will permit? I'm going to Colorado in a few hours (for the rest of the week). But I'll check in frequently to see what is going on. If we can present contradicting data (to support otherwise unsupported statements), everyone will benefit.

Also, I'm a little curious about your findings regarding knock status since the logging rate of the BT tool is what, 20 samples/sec? And the rate of engine events at 6000rpm is 100 events per second. Seems to me that it misses a lot of the action. And I have data that seems to back that up as well.

I'm also interested with what you said with regards to ignition retard "reaction" with respect to nominal ignition advance. For a number of reasons because I've done quite a bit of testing in this field. Easy to do when our tuning device can actually adjust DME perceived nominal ignition advance. Looking forward to your elaboration.

Cheers,
shiv
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      07-16-2009, 03:36 AM   #40
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Quote:
Originally Posted by shiv@vishnu View Post
Looks like Whitesled is banned for being naughty so I don't think he's saying much. But yes, for the last several months the PROcede has been adding 2-3 degrees of timing during light cruise conditions. This improves fuel economy by 2-5mpg depending on cruise RPM.

Shiv
Hi Shiv,

What makes me sceptical about adjusting timing is that when I first installed your maps with increased cruising mpg I noticed a large improvement at the FIRST run. I have never seen the low mpg I had initially again. To me this indicate that the ECU adjusts and override the Procede ignition adjustments medium and long term.

A comment on this would be interesting, br
/Tobias
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      07-16-2009, 06:00 AM   #41
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Quote:
Originally Posted by Tobias1980 View Post
Hi Shiv,

What makes me sceptical about adjusting timing is that when I first installed your maps with increased cruising mpg I noticed a large improvement at the FIRST run. I have never seen the low mpg I had initially again. To me this indicate that the ECU adjusts and override the Procede ignition adjustments medium and long term.

A comment on this would be interesting, br
/Tobias
It doesn't override the extra ignition advance and this can be verified with a simple datalog of Ignition Advance during cruise.
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      07-16-2009, 06:15 AM   #42
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Quote:
Originally Posted by shiv@vishnu View Post
It doesn't override the extra ignition advance and this can be verified with a simple datalog of Ignition Advance during cruise.
Also on medium and long term?
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      07-16-2009, 07:18 AM   #43
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Thank you, Shiv
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      07-16-2009, 07:40 AM   #44
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Quote:
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Also on medium and long term?
Absolutely. Easy to verify as well.
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