Hi. I thought it might be good to start my own thread instead of derailing someone elses. This will (likely) be a story of how to blow up a perfectly good Audi 3.0TDI.
Firstly heres a link to my old build thread form few years back. Some of you oldtimers might still remember it.
http://forums.tdiclub.com/showthread.php?t=176063&highlight=litle
Ok. Lets begin.
I bought the car pretty much year ago. It stayed stock for surprisingly long time. I read the original file while driving home from the shop, but I didn't mod the file untill next day.
The car in question was a 2006 model Audi A6 with Tiptronic box. It had some dents and crappy crash repair work done, but since the price was right I dared to take it. Car had 345k km on the clock but the engine was already changed once and that supposedly had 100k less on it.
After chipping it I just drove it for a while and did some repairs. The gearbox acted up when cold, so I changed the oil and filter. The result was decent operation while cold, but twitchy change from third to second when it was warm... Luckily after a month or so the blob of junk decided to move from the valvebody and the box repaired itself.
Another repair I did was a injector service. I sent a spare set to Romania, and got a repaired set back in a week or so. Don't know what they did to them, but they seem to work better than before so I can't complain. Those will propably be just a temporary fix anyway, since the original injectors aren't going to cut it after a point. Too small.
Ok. Lets start with the fun part. Ruining the car that is.
As I know myself I knew that upgrading the turbo would be just a matter of time. But somehow I just didn't like the idea of stock based hybrid turbos. They have limitations and would not get me the air I will need.
So I had few options. GT3576VKLR or BV S200V/S300V. After carefully measuring (read guessing) the available space, I opted for the phisically smallest of them. S200V. The problem with that was that it had crappy 45/68mm compressor mated with what seemed to be perfect size turbine. So the turbo went to Finturbo and they measured out what could be done with it. The end result was 11 blade compressor with 50mm inducer and 72mm exducer. If the profile is anything like a real GTX would be it should be good for wee bit over 400hp.
I started the turbo conversion few weeks ago. After alot of cutting, grinding, welding and cursing the turbo sat pretty much where stock turbo did. I used stock exhaust manifold Y/support and welded a suitable flange to it. I kinda cheated a bit here and tilted the turbo slightly so that the exhaust is pointing slightly down and compressor inlet up. To everyones surprise it won't even touch the hood when its closed
On the other hand servo connector wasn't so lucky. After first test drives it broke off after hitting the firewall...
So how does it work. Bit slow on spooling under 2500rpm. That might still get better after some tuning tough. With vanes fuly open the boost creeps like no other. At around 4000rpm the boost is close to 3bar. EMP is around 3.2bar so no worries there. The solution to the boost creep is waiting on the mail to be installed this weekend. Tial MV-S copy wastegate. That should do the trick and hopefully it will last for a while.
Now that I have a turbo that is capable of delivering boost without the back pressure getting sky high I fould out few things about these cars. I have tuned few of these with stock based hybrids the power has been somehow limted to 300hp or so. The MAF values have beend dropping after 3000rpm thus dropping the IQ. I just thought that the turbos weren't all that good and that the aiflow was limited nearly to stock turbo levels. But now that I have a turbo that is boosting nearly 3bar and the freaking MAF values were still dropping to 1100mg at 4200rpm! So today I did some testing and with VCDS Generic OBD I was able to log airflow in g/s. The result was 249,98g/s with anything over 1.7 bar. That leads to 900kg/h max maf value and that just isn't nearly enough. freaking 33lbs/min! No wonder the cars delivered roughly 300hp with lamda values set to 1-1.1.
So now I need to either bend the lamda maps at high ariflow or get a larger MAF and try to get the linearization correct. I think I would need almost 50% more flow range with the sensor to be able to properly controll the fueling in all situations. I think first I will just tweak the lamda maps tough.
And at the end few crappy pictures of the build.
Firstly heres a link to my old build thread form few years back. Some of you oldtimers might still remember it.
http://forums.tdiclub.com/showthread.php?t=176063&highlight=litle
Ok. Lets begin.
I bought the car pretty much year ago. It stayed stock for surprisingly long time. I read the original file while driving home from the shop, but I didn't mod the file untill next day.
The car in question was a 2006 model Audi A6 with Tiptronic box. It had some dents and crappy crash repair work done, but since the price was right I dared to take it. Car had 345k km on the clock but the engine was already changed once and that supposedly had 100k less on it.
After chipping it I just drove it for a while and did some repairs. The gearbox acted up when cold, so I changed the oil and filter. The result was decent operation while cold, but twitchy change from third to second when it was warm... Luckily after a month or so the blob of junk decided to move from the valvebody and the box repaired itself.
Another repair I did was a injector service. I sent a spare set to Romania, and got a repaired set back in a week or so. Don't know what they did to them, but they seem to work better than before so I can't complain. Those will propably be just a temporary fix anyway, since the original injectors aren't going to cut it after a point. Too small.
Ok. Lets start with the fun part. Ruining the car that is.
As I know myself I knew that upgrading the turbo would be just a matter of time. But somehow I just didn't like the idea of stock based hybrid turbos. They have limitations and would not get me the air I will need.
So I had few options. GT3576VKLR or BV S200V/S300V. After carefully measuring (read guessing) the available space, I opted for the phisically smallest of them. S200V. The problem with that was that it had crappy 45/68mm compressor mated with what seemed to be perfect size turbine. So the turbo went to Finturbo and they measured out what could be done with it. The end result was 11 blade compressor with 50mm inducer and 72mm exducer. If the profile is anything like a real GTX would be it should be good for wee bit over 400hp.
I started the turbo conversion few weeks ago. After alot of cutting, grinding, welding and cursing the turbo sat pretty much where stock turbo did. I used stock exhaust manifold Y/support and welded a suitable flange to it. I kinda cheated a bit here and tilted the turbo slightly so that the exhaust is pointing slightly down and compressor inlet up. To everyones surprise it won't even touch the hood when its closed
On the other hand servo connector wasn't so lucky. After first test drives it broke off after hitting the firewall...So how does it work. Bit slow on spooling under 2500rpm. That might still get better after some tuning tough. With vanes fuly open the boost creeps like no other. At around 4000rpm the boost is close to 3bar. EMP is around 3.2bar so no worries there. The solution to the boost creep is waiting on the mail to be installed this weekend. Tial MV-S copy wastegate. That should do the trick and hopefully it will last for a while.
Now that I have a turbo that is capable of delivering boost without the back pressure getting sky high I fould out few things about these cars. I have tuned few of these with stock based hybrids the power has been somehow limted to 300hp or so. The MAF values have beend dropping after 3000rpm thus dropping the IQ. I just thought that the turbos weren't all that good and that the aiflow was limited nearly to stock turbo levels. But now that I have a turbo that is boosting nearly 3bar and the freaking MAF values were still dropping to 1100mg at 4200rpm! So today I did some testing and with VCDS Generic OBD I was able to log airflow in g/s. The result was 249,98g/s with anything over 1.7 bar. That leads to 900kg/h max maf value and that just isn't nearly enough. freaking 33lbs/min! No wonder the cars delivered roughly 300hp with lamda values set to 1-1.1.
So now I need to either bend the lamda maps at high ariflow or get a larger MAF and try to get the linearization correct. I think I would need almost 50% more flow range with the sensor to be able to properly controll the fueling in all situations. I think first I will just tweak the lamda maps tough.
And at the end few crappy pictures of the build.
