Audi TT 3.2 Turbo Project
One of our personal project cars is the Audi TT 8j equipped with the 3.2 vr6 engine and a dq250 dsg gearbox. Since no one can be satisfied with just 250ps or 270ps on this excellent platform we decided to skip the engine modifications that are based on the stock Naturally aspired engine and go directly for a Forced induction build.
Our target is a daily usable car with 600 to 650 hp and factory reliability. we have decided to upgrade all the weak links and points of this engine by forging the internals and replacing all the used parts(123.000km) with new OEM quality or higher .
Parts are coming in daily and this is only a small amount of them as they came first. Our choices are coming mostly from well respectable brands local and overseas as we need to get the emissions approval from our local government to use the car daily. A small description from the aftermarket parts that we chose for a lot of reasons will be written below.
- Precision 6466 Gen 2 Ball Bearing Turbo
- Rothe cast iron Exhaust manifold
- Rothe cast aluminum Intake manifold
- Tial External Wastegate 44mm MV-S watercooled
- King Racing main Bearings
- DW65V 265 lph PNP quattro Fuel pump
- ZRP Connecting Rods
- Wiseco 9:1 pistons
- OEM Head Gasket
- ARP Cylinder head and Block Studs
- Bosch 980cc Injectors
- Fmic Intercooler Treadstone Performance TR10C
- ATI Cranckshaft Fluid Damper
- Vw Golf 4 R32 Fuel rail 022133317K
- Upgraded maf sensor housing 077133471K
In case you need to lower your compression with adding only a gasket/spacer and keep stock internals here is which part numbers you need. Those gaskets/spacer can be found on ebay.
- Verdichtungsverhältnis 10.9:1 Serie (0,65mm) Ebay Nr. 190938687669
- Verdichtungsverhältnis 10:1 bei Gesamtstärke 1,65mm Ebay Nr. 190938700242
- Verdichtungsverhältnis 9.6:1 bei Gesamtstärke 2,15mm Ebay Nr. 200977742350
- Verdichtungsverhältnis 9,2:1 bei Gesamtstärke 2,65mm Ebay Nr. 190938693516
- Verdichtungsverhältnis 8,9:1 bei Gesamtstärke 3,15mm Ebay Nr. 190571970262
- Verdichtungsverhältnis 8,6:1 bei Gesamtstärke 3,65mm Ebay Nr. 190571971216
- Verdichtungsverhältnis 8,0:1 bei Gesamtstärke 4,65mm Ebay Nr. 200769295850
The Engine
It`s about time to strip down the car and start working on our engine and peripherals.
The engine assembly is the most important procedure and has to be executed with precision and accuracy in every point. Our block was bored and honed to the new piston specifications.
The ATI Fluid damper is one key upgrade for this engine as the stock pulley is very weak and does not provide sufficient balancing for a high revving turbocharged engine.
Now that the engine is assembled we will install our cylinder head and move on with the intake and exhaust manifold fitments as well as the turbo and the external wastegate.
The Exhaust system.
We decided to build the half part of the exhaust system based on an 80mm stainless steel piping of the finest quality. So here we go…
All the parts from our car were custom welded in house by us using only the finest quality to ensure the longevity of our build.
Our exhaust was build in 2 phases and this one will be the one that we are going to use on the drag strip as it does not conform with the local emission laws since we are not using any catalytic converters. Our downpipe though will remain the same for both cases.
Lets move to the down pipe as that was build after we fitted the new forged engine in order to have the correct angles and spaces from both the turbo and the external waste-gate actuator.
You can see that despite the dual lambda system we installed only one in our downpipe and that is not something that everyoneE7.1.1 engin could do.The Bosch Me management system has two primary banks to control the afr/mixture of the engine(B1S1 & B2S1).
If someone installs both primary lambda sensors to one pipe without doing some custom asm patching/coding to the original ecu firmware/software, the fuel trims will eventually go out of control while having a +25 to -25 difference to each other.
This will cause many problems to the functionality and performance of your engine so if you are not able to purchase our special code, please use a different exhaust manifold that supports dual(stereo) lambda sensors.
Basically the software is not designed to use only one bank(side B1s1 – B1s2) and by disabling that manually the second bank(b2s1 – B2s2) will have incorrect injection timing.What we do by patching the oem firmware code with our own modifications allows the ecu to use the same fuel trims for both banks thus both sides of the engine.
This is our finished down pipe including a lambda probe and an egt sensor which will be utilized later .
The Intercooler
Now that our exhaust side is finished we will continue with our intake side by building the intercooler piping and fitting the intercooler in front. We used aluminum for every application/modification to avoid adding weight to the car. Our goal intercooler comes from Treadstone performance and the model is TR10C capable of 660hp.
This intercooler was the best choice not only for our target horse power but because the space between the bumper and the stock radiators is limited. The centered 76mm inputs are just at the right spot without interfering with any other parts.
The injectors
Although our injectors are not a direct fit to the engine wiring harness and cylinder head we needed to have a reliable solution that exists on the market with a Bosch serial number that can be registered for our TUV inspection.
The 980cc injection quantity is more then enough to feed our engine properly and our injectors are also capable of maintaining a correct spray pattern and a normal idle after some slight modifications/additions on the nozzle side.
OEM vs Upgrade just for comparison purposes.The aluminum fitting was later drilled and inserted in the front side of the injector(nozzle).
We had to purchase wiring adapters to convert our oem injector plugs to normal EV6 type in order to connect that with the main wiring harness.
After some new findings on the net and since a company produced the correct size for direct fitment on these engines again with 980cc and one hole spray pattern. We decided to swap again our injectors with those before we even make our first start.
We are definetly go to go with the fitment and since we are closing in finishing up with the hardware here are some more detailed pictures of the installation.
The new and bigger DSG oil cooler (3 rows mores then stock).
S8/S6/S4 4.2 Mass air flow sensor coming from the turbocharger.Inner diameter is 82.78mm and part number is 077-133-471k
Fuel lines for the new fuel rail.
Side piping from turbo to the inter-cooler with relocated stabilizer bar arm and a custom piping holder.
Everything was fully welded after the final fitment tests.Over all progress of the engine bay.
More detailed pics in our water cooled tial external wastegate installation and water pipes. Also car started for the first time after the build and there will be some videos soon..
After our first settings and in the engine management system and a boost level of 0.6 bar our car performed excellent after the breaking in period of our new built engine.The stability of the graph and the powerband shows the potential of the next stage that will come after a small period of driving and making sure car has no leaks or crucial issues with the hardware modifications.
474ps and 583nm is the first ever measurement of our new engine which maintains the stock 3.200 cubic capacity.Engine i running in very safe afr and boost levels and we will start raising the power once everything is 100% finished. In the meantime we are planning to upgrade our braking power by using the bolt-on TTRS 8J Calipers.
To be continued…