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Author Topic: MED9 Timing Retardation  (Read 23002 times)
groovetek
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« on: December 15, 2010, 10:26:59 PM »

Just wondering with MED9 cars, VW's Passat R36, Audi S5/RS4, etc. if there should be any timing retardation when under full throttle?

I was under the impression that, similar to ME7 with the 2.7TT for instance, that timing retardation is the same as "correction factor", and that this should be greater than 0 when going for an open throttle run.

Any input?  I am trying to diagnose whether or not a customer's car was properly returned to stock or not.  He was dissatisfied with the lack of gains from a particular tuner's ECU program, and after they returned his car to "stock", his fuel consumption has suffered and I believe they purposely put on a file with very relaxed ignition timing curves.

Anyway, at no stage while going full throttle does the timing retardation ever go above 0.  Is this normal for MED9 cars?
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nokiafix
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« Reply #1 on: December 19, 2010, 02:15:03 PM »

Just wondering with MED9 cars, VW's Passat R36, Audi S5/RS4, etc. if there should be any timing retardation when under full throttle?

I was under the impression that, similar to ME7 with the 2.7TT for instance, that timing retardation is the same as "correction factor", and that this should be greater than 0 when going for an open throttle run.

Any input?  I am trying to diagnose whether or not a customer's car was properly returned to stock or not.  He was dissatisfied with the lack of gains from a particular tuner's ECU program, and after they returned his car to "stock", his fuel consumption has suffered and I believe they purposely put on a file with very relaxed ignition timing curves.

Anyway, at no stage while going full throttle does the timing retardation ever go above 0.  Is this normal for MED9 cars?

I work with med9 Tfsi engines and stock and with good fuel they tend to run 0cfs, maybe 1-2cf after a good turbo cooking thrash to get the temps sky high.  They are an easy engine to stage 1 tune even a poor map with just 20% on the LDR will yeld good power.  The down side to the Tfsi engine is the early stock DV having splits in the rubber and the plastic one way check valve in the PCV not working.  I would say 7 out of 10 Tfsi I tune will have issuse with the dv or pcv.  And if the tuner have added more boost the dv could have split even more which would make the car feel slower when the stock map has been reflashed.

With any stage 1 or 2 maps I would like to see CFs of between 2 - 3.5 so I know I am getting as much advance as I can without detting hell out of the engine.  I have seen many 2.0tfsi and 1.8t run far too little advance and getting stupid egt and cherry red manifolds then looking in to the mapping they have just pulled -% off the higher load points of the ignition maps.   My own 1.8T pulls around 3 - 4.5CFs at the top end, and with the knock sensors swithced off and set in to development mode via the mapping and then my det cans connected we could not hear any signs of det.  Its when we added 8deg to the AIT  ignition off set mapping and managed to get Cfs of 9-11 so we could hear via the det cans.
With any tune the timing is just as important as the lambda control, its just not a lot of tuners full understand it or they are worried about.

I tend to tune most of my ignition via the AIT offset maps which allows for optinum advance at optinum charge temps.  It just takes a lot of time logging and getting right.
« Last Edit: December 19, 2010, 02:29:47 PM by nokiafix » Logged
ArgDub
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« Reply #2 on: December 19, 2010, 04:30:21 PM »

Thats interesting, I know knock sensor programming is pretty smart, but I've always wondered how conservative it is. Could you explain that difference in terms of net advance, power and torque you experience in your 1.8t when the ecu is pulling 12 compared with normal 3 or 4.
« Last Edit: December 19, 2010, 04:32:15 PM by ArgDub » Logged
nokiafix
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« Reply #3 on: December 19, 2010, 04:57:32 PM »

Thats interesting, I know knock sensor programming is pretty smart, but I've always wondered how conservative it is. Could you explain that difference in terms of net advance, power and torque you experience in your 1.8t when the ecu is pulling 12 compared with normal 3 or 4.


By going mad and adding extra advance via the AIT off sets gave high CFs of upto 12s, along with a lambda closer to 11:1 vs the 12.2:1 with CFs around 3. Power losses are only seen after 5500rpm of around  8-10bhp.  The strange thing is that I would have thought that the bulk of the correction would be on the peak of the torque around 3300prm and 1.5bar spike where the flame front is much faster, but at this point it was only pulling CFs of 6 max, only after 5500rpm did the Cfs go to 12?
Peak torque is 260lbft@ 1.5bar and 246bhp 1,1bar  with 9.5:1cr
We only started playing with the knock sensors a few weeks back and i would like to spend a few more hours finding all the timing offsets and setting them to zero and only having  one ignition map and one ait offset to use during mapping, in theory we coulfd extact data from our Omex d600 ecus and use them against the load v ignition maps in the me7.5.
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Rick
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« Reply #4 on: December 21, 2010, 03:24:27 PM »

Above it sounds like you need to adjust the timing map based on rpm rather than just adding via the air temp.

Also, a question re the correction factors.  You said you switched off the knock sensors, and when you hit a correction factor of 9-11 you could hear det. Does this mean with the knock sensors turned off VAGCOM still reads the CF?  I can't see how this would work.  Or is it that you got to a CF of 8-11, then turned off the knock sensor and listened?

Rick
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nokiafix
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« Reply #5 on: December 22, 2010, 02:03:44 PM »

This was playing on the rolling road not mapping session, the car runs a perfect ignition map.  By turning off the knock control  and using the ait offset allows for a better insight on development,  we can heat soak the intercooler and get the ait to where was and the and knowing exactly the effects.

When mapping we will write a base map which will be 3-4kw under the CFs, then between ait temps of 20c 40c will will apply 4kw correction to optimise the timing. Its point less having a really good timing map that being over or under corrected via ait. Plus its a safer way to turn for the summer months as over 50c we  pull the timing back.
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hammersword
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« Reply #6 on: December 22, 2010, 08:54:57 PM »

The most important on Advance timing on newer motronics as ME7 or MED9 is the knock control. As stock the knock control is calibrated via Bosch for fuels like 90-91 octanes!
So, if you like to use 100octane fuel, the increasing timing maps only will not help at all to get more timing.

You MUST calibrate the whole knock control for the new fuel. That includes knock sensor sensitivity, knock filters, knock window where knock starts to hear, reference sounds etc!

Especially when forged pistons added and they produce higher noise on cylinders, that always confuse knock control and starting CFs as it thinks of detonation. So then you have to calibrate reference sounds and knock filters

Knock control is something very complex but it will give you power!

For example I keep 19.5degrees on S3 2.0TFSi Stage 2nd (with pump) with 2.1bar overboost and 1.27 at 7000!
If we add water -meth on that I have to calibrate again knock control and give the extra timing on the engine
Smiley

The advance timing on ME ecus is not only increasing KFZW and KFZWOP by 3 or 2 or 5!
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nokiafix
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« Reply #7 on: December 23, 2010, 03:13:30 PM »

The most important on Advance timing on newer motronics as ME7 or MED9 is the knock control. As stock the knock control is calibrated via Bosch for fuels like 90-91 octanes!
So, if you like to use 100octane fuel, the increasing timing maps only will not help at all to get more timing.

You MUST calibrate the whole knock control for the new fuel. That includes knock sensor sensitivity, knock filters, knock window where knock starts to hear, reference sounds etc!

Especially when forged pistons added and they produce higher noise on cylinders, that always confuse knock control and starting CFs as it thinks of detonation. So then you have to calibrate reference sounds and knock filters

Knock control is something very complex but it will give you power!

For example I keep 19.5degrees on S3 2.0TFSi Stage 2nd (with pump) with 2.1bar overboost and 1.27 at 7000!
If we add water -meth on that I have to calibrate again knock control and give the extra timing on the engine
Smiley

The advance timing on ME ecus is not only increasing KFZW and KFZWOP by 3 or 2 or 5!

And this is why we are using detcans direct to the block for development, I think next near I will be running the car on the road without any knock control at all.
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hammersword
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« Reply #8 on: December 23, 2010, 07:59:32 PM »

My friend the Motronic knock control is so smart that you can do anything! If you know how to calibrate it of course!

The detcan is something new and quite interesting
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kelesha
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« Reply #9 on: December 24, 2010, 02:35:06 PM »

The most important on Advance timing on newer motronics as ME7 or MED9 is the knock control. As stock the knock control is calibrated via Bosch for fuels like 90-91 octanes!
So, if you like to use 100octane fuel, the increasing timing maps only will not help at all to get more timing.
Mate, knock noise is same with 90-91 or 120 octane fuel, so if you "calibrate" it for different fuel, you simply reduce knock control sensitivity nothing more Wink 

For example I keep 19.5degrees on S3 2.0TFSi Stage 2nd (with pump) with 2.1bar overboost and 1.27 at 7000!
"keep" you mean that you have 19.5degrees timing on peak torque (2.1bar boost) point ? 
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hammersword
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« Reply #10 on: December 25, 2010, 12:17:04 PM »

Mate, knock noise is same with 90-91 or 120 octane fuel, so if you "calibrate" it for different fuel, you simply reduce knock control sensitivity nothing more
Not only sensitivity, but step retard, and some filters!
Less octane fuel will detonates faster and randomly in the chamber

19.5degrees timing on peak torque (2.1bar boost) point
lol, of course NO. I mean at high RPM
Smiley

The docs that Bosch gives to VW explains perfect how the knock control work.

Changing only sensitivity maps is quite wrong, the engine can easily be damaged and an experienced eye will understand a  lot via VCDS knock voltage block!
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kelesha
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« Reply #11 on: December 25, 2010, 01:03:38 PM »

The docs that Bosch gives to VW explains perfect how the knock control work.
Ok i have these "docs" but inside i cant find explanation for that example from reality......tuned 1.8T ME7 car with GT30 turbo in example, all is fine on dyno AFRs and ignition are perfect, zero CF on VCDS, then you try to test it on highway, and the car start to show a lot of knocks after every fast gearchange, if you change the gears slowly no problem, but fast change cause retard, how you can explain that because it hapen often Wink
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fredrik_a
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« Reply #12 on: December 25, 2010, 04:30:51 PM »

and the car start to show a lot of knocks after every fast gearchange, if you change the gears slowly no problem, but fast change cause retard, how you can explain that because it hapen often Wink


Do you give enough tip in fuel enrichment based purely on swift throttle angle change? A standard wide band lambda sensor is not fast enough to spot that the engine is running lean after a quick gear change so you will not be able to spot it "manually" whilst driving on the road looking at an AFR monitor...
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hammersword
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« Reply #13 on: December 26, 2010, 04:56:48 AM »

what about clutch protection on ME7? There is a map "Advance timing during gear shift"
but I am not sure if that retardation appears as CF!

On your situation may engine produce high noise when you add forged pistons so you have to calibrate optimal noise. That is quite hard procedure as you have to find where the engine make these noises and set the knock to hear there and tell to knock that these noises are not knocking.

 Smiley
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kelesha
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« Reply #14 on: December 26, 2010, 05:03:45 AM »

Do you give enough tip in fuel enrichment based purely on swift throttle angle change? A standard wide band lambda sensor is not fast enough to spot that the engine is running lean after a quick gear change so you will not be able to spot it "manually" whilst driving on the road looking at an AFR monitor...
No, tip enrichment is not the problem in these cases, problem is other Wink But anyway on ME7 tip enrichment is very complex thing, i spend a lot of time to find out all the maps needed, but after many tests i leave them stock, that way tip enrichment work best
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