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Old 8th November 2020, 12:50 AM
ainarssems ainarssems is offline
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Default A8 D3 4.2TDI remap

Before I get on to D3 I will start with a bit of background.

My first adventure into the remap was with C5 A6 in 2011. It was a bit of the task as the EDC 15VM+M ECU found in 2.5TDI is not well documented and also the engine is not known to be most reliable. Anyhow after the lot of time spent researching and lot of trial but not that much of error I did tune it to estimated 225HP and 445Nm from the stock 180 and 370, it was never tested and verified so could have well been a lot less. The way I tuned it and asked some more experienced tuners to review it definitely raised some eyebrows and many said it's a sure way to blow up the engine or melt turbo.
I made it more like petrol engine and raised rpm, the stock max torque is 370 Nm 1.5k rpm to 2.5k rpm, I made it about 445Nm 2.5k to 4.4k and the stock was severely cutting power at after 4.4k but my tune was still going strong to 5k and then cutting at 5.3k. Here I am 9 years later still running fine with 100k on the engine since the tune and almost 250k total which is almost unheard for early V6 2.5TDI without roller rocker arms on the factory camshafts as most fail well before 150k and many even before 100k. Obviously cam wear has nothing to do with tune but still great effort from the engine and while the cams are quite worn by now I have again modified tune slightly to help with air delivery and also lowered smoke limiter to help with torque before the turbos kick in as I do not really care now if the car blows up as it's £500 worth at best now and I would rather send it off with fireworks than scrap it because it cannot pass MOT because of rust or too much suspension problems.

Now back to D3. I have looked at several options including tuning box, generic remap, custom over net, rolling road map and DIY. I am not going into too much detail at the moment but that's a possibility if anyone wants to hear about my thought process. DIY or semi DIY was always the front runner because of cost. I had to upgrade my tool as my last £6 tool I used on A6 would not do D3 so I bought a clone FG Tech V54 for £38. Just to be clear I am not promoting any pirated/clone tools and anyone should decide for themselves and realise that if something goes wrong you are on your own. But paying £700-4000 for a genuine tool is also not what you want to do for 1or 2 of your own cars so may be better to take them to professionals.

Anyhow I have secured several tuning files for 4.2TDI for different soft versions (attached). I have 382247 in my car, I have attached stock and stage1 files for this from online tuner, the tuned file cost me £15, the tuned file should be good for 770Nm, 370HP. The other soft version 392905 tuned by Swiftec should be good for 800Nm, 380HP, I got this online for free.

I have had a quick look at both and I do see some differences in approach between both in boost pressure and also fuel rail pressure. I have not spent much time reviewing them. But I will certainly be combining info from both and then pushing it a bit. The 382247 stage1 provider suggested 750Nm and 370HP is the limit for the exhaust and DPF and while he offered a custom map for £45 he said if I push it higher at stock the pressure and
EGT will rise and ECU will cut back fuel and power if EGT gets too high. He can modify EGT maps to ignore it but that could severely reduce life of items on exhaust side like turbo. I obviously take any suggestions on board but there is a difference between going full throttle for 5 sec at 80mph or trying to set a new record on Nürburgring so I will definitely push the limits and aim for 400+HP and 890-900Nm while keeping all stock.
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File Type: zip A4_D3_4.2TDI remap.zip (739.6 KB, 370 views)
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Last edited by ainarssems; 9th November 2020 at 11:52 AM. Reason: adding attacement
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Old 8th November 2020, 03:17 PM
ainarssems ainarssems is offline
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To follow up on this I will go through some maps and try to explain some things that are modified for the persons that are interested, the general principle will apply to most diesels but while some things my be similar on petrol there are also a lot of differences.

If anyone wants to have a look they can download the free demo version of WinOLS software and have a look at files themselves. It's probably the most used and most versatile soft available. They have dialled back demo soft somewhat these days and limited functionality. In earlier days you had a lot more functioning demo soft that only did not allow to export finished files but since people found a way of extracting files the limited other functions in demo. Anyway still a great soft. https://www.evc.de/en/download/down_winols.asp

The first thing I would like to address is where it all starts with the driver input at the pedal. So basically the ECU needs to translate the accelerator pedal position (learned position) into the torque value in case of EDC16/EDC17 or injection qty in mg in case of older EDC15. I will talk about 4.2TDI which has EDC16CP34 so it will be Nm.


There is a map or to be more precise several maps that translate pedal input to requested Nm, it could be several maps for normal, limp mode, reverse and so on. There can also be several blocks of the all the maps in the same ECU for different codings. For example my 2.5 TDI has 2 blocks depending on coding 1 for manual and 1 for auto but A8 only 1 block.

So if we have a look at main drivers wish map it has 2 axes of engine rpm and pedal position and and output of Nm. This is the stock map for my soft version in text and 3D. On the text version you have % of learned throttle going horizontally and rpm going vertically and the grid as the requested Nm depending of rpm and throttle position. This is only what the driver requests, not the actual torque that engine will be delivering as that will be limited by a number of other maps and factors. You can also see that it goes to 0 Nm at 5200rpm with the torque reducing rapidly from 4400 to 5200rpm. If you feel a bit adventurous and want to take the risks you could change that like I did on A6 and have nearly full torque up to 5300rpm and the a drastic cut from 5300 to 5500 rpm. The A6 does the rev limiter bounce like the petrols do and not the gradual fade out you normally get on diesels, but this will be affected by a number of other maps as well.





We can see that original map is already going up to 840 Nm so you do not really need to modify it if you do not want to go over 840Nm and you do not want to modify throttle response.

Now if we have a look at the modified files you will see that tuningfilewarehouse £15 file for my soft version 382247 goes up to 900Nm



and Swiftec version for soft version 392905 goes to 1000Nm



Like I said this is what the driver requests, not the actual torque engine will make as that will be limited by a lot of other maps and factors but if you don't ask you don't get.

I will address main torque limiter in the next post.
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Last edited by ainarssems; 8th November 2020 at 03:49 PM.
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Old 9th November 2020, 07:01 AM
jonnypym123 jonnypym123 is offline
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Intresting stuff, I might be downloading WinOLS and taking a look. I had my A8 4.2tdi D3 remapped on stock hardware and was down on power on the dyno 300hp 630nm took it to the Perfomance Centre in Sunderland, they upped it to 340hp 866nm, which if I honest looking back was disappointing however they thought it was to do with carbon build up but I wasn't sure. looking at a lot of dyno video for the A8 4.2tdi BVN the car seems like 340-360 peak is about right for stock hardware with everything intact. Since then I removed the dpfs and egrs and removed the silencers, changed the glow plugs and fitted a new clean top manifold and oil service and BMC air filters and it feels faster to when it was only remapped I think, I'm doing the swirl flaps next when I get some time off. The max peak hp I've seen dyno proven without modifying the turbos is around 385hp dyno proven, theres some claim 430+ on the D3 without uprgading turbos but I dont think thats possible, if you upgrade the turbos yeah, those figures probably only possible on the d4 as they have upgraded compressor wheels and upped rail pressure as standard along with different intercoolers and gearbox. Hope the tuning goes well and will be interesting watching your progress

Last edited by jonnypym123; 9th November 2020 at 07:11 AM.
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Old 9th November 2020, 12:32 PM
ainarssems ainarssems is offline
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Quote:
Originally Posted by jonnypym123 View Post
Intresting stuff, I might be downloading WinOLS and taking a look. I had my A8 4.2tdi D3 remapped on stock hardware and was down on power on the dyno 300hp 630nm took it to the Perfomance Centre in Sunderland, they upped it to 340hp 866nm, which if I honest looking back was disappointing however they thought it was to do with carbon build up but I wasn't sure. looking at a lot of dyno video for the A8 4.2tdi BVN the car seems like 340-360 peak is about right for stock hardware with everything intact. Since then I removed the dpfs and egrs and removed the silencers, changed the glow plugs and fitted a new clean top manifold and oil service and BMC air filters and it feels faster to when it was only remapped I think, I'm doing the swirl flaps next when I get some time off. The max peak hp I've seen dyno proven without modifying the turbos is around 385hp dyno proven, theres some claim 430+ on the D3 without uprgading turbos but I dont think thats possible, if you upgrade the turbos yeah, those figures probably only possible on the d4 as they have upgraded compressor wheels and upped rail pressure as standard along with different intercoolers and gearbox. Hope the tuning goes well and will be interesting watching your progress

That's a lot of torque for not that much of power, not something you would expect. Stock engine has 650Nm 1800-2500 rpm and 326 HP at 3750 rpm which would be 620Nm at 3750 rpm. If your peak HP were at the same point as your max torque it would be max power at 2790 rpm. Or if your maxpower was at 3750rpm then it woulfd be 650Nm at 3750. So something was cutting torque a lot as rpm went up, could be restriction in intake or exhaust, exhaust gas temperatures getting too high or not enough fuel delivery - blocked fuel filter or weak fuel pump. Did you have picture/ printout from dyno? Or maybe they did what's called 'economy map' where you get a lot of torque only at low rpm to encourage upshifting ang keeping highest possible gear. For example 700nm at 4k rpm is 393HP. Maybe they went too high with torque, EGT got too high and ECU cut fuel to reduce EGT before it got to max power. Did they do any logs while on dyno - EGT's or DPF pressure differential, fuel pressure, lambda? You are a bit too far, otherwise I would have been interested to read the file from your car and see what they have done.

From what I heard it's the DPFs and exhaust limiting how much power you can get. Push too much and exhaust gas temperatures and back pressure goes too high and cuts the power. Without DPF and more freeflowing exhaust it should be good for 420-450HP and then you run into what turbo and fuel pump can do and then soon after also intercoolers and injectors. you do not need bigger turbos to get more air to reach 450, it's more about how much exhaust can you get through them without them getting too hot or spinning too fast and reducing life severely. I am in no rush getting it mapped, just having a look at different tuning approaches in the tuned files I have got and then will make a decisions what I will do and how far will I push it, .Will start a bit safe and gradually increase while monitoring EGT and DPF differential pressure, might raise EGT maps a bit if required but not completely flatten like some tuners do.
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Old 9th November 2020, 01:01 PM
ainarssems ainarssems is offline
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I will have a look at main torque limiter map now.

The horizontal axis is rpm and vertical is atmospheric pressure, output is torque limit in Nm. You do not normally need to worry about the pressure unless you live in mountains, then it uses the lower value lines at high altitude to protect turbos. All we are interested in is 900mbar line which is use up to about 3000ft/1000m altitude.

This is stock map going up to 670Nm



This is tuningfilewarehouse map going to787Nm


And this is Swiftec map going to 820Nm
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Old 9th November 2020, 01:34 PM
jonnypym123 jonnypym123 is offline
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I've attached the dyno graph, it has always made me wonder how the torque went to 866nm peak but hp was only 340hp peak, surely this would have increase proportionatly who knows. I did at the time of the remap had a completely stock exhaust so could of been a safe EGT tune, since then the exhausts are completely empty bar the precats off the turbos, which I can imagine are difficult to get off.
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Old 13th November 2020, 11:08 PM
ainarssems ainarssems is offline
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I am not sure, maybe I have been going in too much detail here, I do not really get into full remap guides as there are plenty resources already online. So maybe I will just stick to my findings and final results. Great forum with lot of info where I got my first knowledge was https://www.ecuconnections.com/forum/, I am attaching a guide for EDC16 from that forum as well if anyone is interested in going into details
Attached Files
File Type: pdf EDC16 tuning guide version 1.1 (1).pdf (250.0 KB, 398 views)
File Type: pdf EDC16C9_v1.4.pdf (6.83 MB, 624 views)
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Old 13th November 2020, 11:42 PM
ainarssems ainarssems is offline
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I have not gone into changing my file yet, still reviewing both tuning versions.
I have found some oddities in remapfilewarehouse file, for example requested max boost has been increased from 2627 mBar to 2685, boost limiter increased to the same value ( normally you would expect it to be slightly higher) but the SVBL (Single Value Boost Limiter ) left at 2650mBar same as stock. First of all their file is rather conservative 370HP, 770Nm so I am not sure if there was any need for increased boost anyway, but because SVBL is not increased there is the risk of limp mode if boost pressure go over this limit for prolonged time. Swiftec map also has boost increased but only at the max injection quantities like you would expect and without damos for this software version I have not found SVBL for it yet.

I can also see that in RFW file rail pressure has been raised a bit at high/mid range but max values are still 1600Bar same as stock, it's probably OK for the modest gains they are doing but Swiftec has raised max pressure to 1700, I think I can go to 1800. I know it's not the greatest pump on this engine and cannot really do much more pressure or delivery rate but should be able to support 1800Bar pressure and deliver up to 450HP (I am not going for 450 with DPF in place and stock exhaust and would be happy if I get 400+), after that car needs stronger pump.

I also found the speed limiter in my file so that's being raised as well, I am probably never going over 250km/h, at least not in UK but it's nice to know option is there if needed.
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Old 28th November 2020, 12:00 AM
ainarssems ainarssems is offline
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Just a bit of warning , when you do remaps things can go wrong and if you do it long enough they will so you need a backup solution. I have not touched A8 yet, mainly because I was still testing my new FGTech Galleto V4 54 to make sure it works OK and to reduce the chances of bricking A8. So well obviously I did brick the ECU on A6 but that's what the stress testing is all about. I am not sure what went wrong, I switched EGR back on, did slight adjustments to start of injection (SOI), fashed file - no start, no connection to VCDS, no connection to Galletto. The reason I chose Galletto was because my old Galletto 1260 was working just fine but it was a bit old and while it could do 4.0TDI dual ECU it could not do 4.2TDI, at least not officially, so I went for newer version. I am not sure about MPPS but I was led to believe that MPPS can only do master ECU through OBD so you either need to do them on bench or swap the places to do slave ECU on 4.2TDI with MPPS, but that can result in another problem with both ECU's thinking they are masters so you end up with only 4 cylinders running. Galletto 4 V54 will do both ECUs correctly over OBD. But what I found out was that if something goes wrong and you need to recover ECU in bootmode Galletto can only read it, not write new(or original) file even when it is in boot mode and on bench so I got myself MPPS as well. It's all good ECU has been recovered on bench with MPPS and it runs fine now, just a thing to keep in mind if you are going DIY route. I am playing a bit cautious as I can afford A6 being out of action couple of days but I really need A8 working every day.
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