Mods
2004 2.5TDI V6-engine (engine code BDG), engine fully rebuilt, balanced, regrinded cams for more lift and duration, inserted valves deeper to the head(also reduced compression as result), ported heads, compound turbocharging S361SXE as low pressure turbo and two K03 as high pressure turbos from Audi 1.8t, electrohydraulic power steering from Opel Astra G, carter 100gph fuel liftpump, modified VP44 fuel pump, everything else but brake fluid/main cylinder is modified or moved. Bigger brakes from the B7 Audi A4, stripped down interior, BC-racing coil overs. Will have VEMS or MAXXecu for logging.
Build story
I had this triturbo compound idea years ago when I still had my single turbo original 99' engine running good. It made pretty good power after all, around 400hp/700nm from the 2.5tdi. Once it break down due broken flywheel it came clear to make new engine. So slowly I started to collect parts I need. It's been almost 2.5years now since the build started. Why three turbos you might ask? Because I can! Well there is also the thing called symmetrical layout. To me having V6 engine compound setup with two turbos sounded odd, somewhat weird piping between the stages. Now it is logical. Both exhaust banks feed the small k03s from the audi 1.8t and those feed bigger borg warner S300SXE between the banks. Sure the intake side is bit complicated since it is opposite to the exhaust. So the big low pressure turbo S300sxe feeds the two small high pressure k03 turbos and they merge up to the big front intercooler and to the engine.
I wanted to go compound setup because I feel i needed more boost since we are bit rpm limited on diesel world. 6000-6500rpm max. Mostly there are no turbos that have great pressure ratios as single stage. Mostly they are off the map after pressure ratio 4, on sealevel that is about 3bar of boost. Last engine had single turbo that I ran around 2.6bars and it felt that i needed more boost. So basically on compound setup if you want 3bar of boost you need both stages have PR2. That means that both stages work on their optimal compressor map area. Matching compound turbos is one of the hardest thing. I have friend who is engineering turbos for tractors etc. So he helped me bit to the right direction. It may be that my small HP turbos are bit too big and large LP turbo is bit too small. Time will tell.
Currently I have only 90% over stock nozzles and modified VP44 pump. Original pump has two 7mm plungers and this one has three 6mm plungers. And also has 1800bar fuel pressure on pump head, so good upgrade compared to stock 1600bar. I used to have 120% over stock nozzles on my last setup but they had some atomization problems. That means excessive smoke. Smoke is something I'm trying to get rid off.
Since there is really not that much space on the Audis engine bay everything is relocated or removed if not needed. For example original power steering is removed and replaced with electrohydralic one from the Opel Astra and moved to the trunk, A/C is removed, original oil/water cooler is removed, custom brackets for the alternator, coolant reservoir and for abs-unit. Also original battery is relocated from the engine bay to the trunk.
Oh not to mention you absolutely have no aftermarket parts available for this engine type. :D So everything is "homemade". Except head work and engine balancing. I really don't know why I have this fixation for this under-rated engine. Maybe it is more satisfying to have top results as underdog. It is now mainly built for drag racing / racing but it will be registered for street use too. Here in Finland it is possible to register your older cars to the streets if they met the specs .
Since this is such a unique build my current goal is just have it running and go out for testing and drive. Since this build has very small budget it has been good trip for learning and also learning manufacturing stuff by myself. I have already ideas what to make different for the next build when the time comes.
I have dedicated page for this build on facebook with lots of photos: https://www.facebook.com/Kingdieselracing and youtube channel https://www.youtube.com/bigdiffas
I wanted to go compound setup because I feel i needed more boost since we are bit rpm limited on diesel world. 6000-6500rpm max. Mostly there are no turbos that have great pressure ratios as single stage. Mostly they are off the map after pressure ratio 4, on sealevel that is about 3bar of boost. Last engine had single turbo that I ran around 2.6bars and it felt that i needed more boost. So basically on compound setup if you want 3bar of boost you need both stages have PR2. That means that both stages work on their optimal compressor map area. Matching compound turbos is one of the hardest thing. I have friend who is engineering turbos for tractors etc. So he helped me bit to the right direction. It may be that my small HP turbos are bit too big and large LP turbo is bit too small. Time will tell.
Currently I have only 90% over stock nozzles and modified VP44 pump. Original pump has two 7mm plungers and this one has three 6mm plungers. And also has 1800bar fuel pressure on pump head, so good upgrade compared to stock 1600bar. I used to have 120% over stock nozzles on my last setup but they had some atomization problems. That means excessive smoke. Smoke is something I'm trying to get rid off.
Since there is really not that much space on the Audis engine bay everything is relocated or removed if not needed. For example original power steering is removed and replaced with electrohydralic one from the Opel Astra and moved to the trunk, A/C is removed, original oil/water cooler is removed, custom brackets for the alternator, coolant reservoir and for abs-unit. Also original battery is relocated from the engine bay to the trunk.
Oh not to mention you absolutely have no aftermarket parts available for this engine type. :D So everything is "homemade". Except head work and engine balancing. I really don't know why I have this fixation for this under-rated engine. Maybe it is more satisfying to have top results as underdog. It is now mainly built for drag racing / racing but it will be registered for street use too. Here in Finland it is possible to register your older cars to the streets if they met the specs .
Since this is such a unique build my current goal is just have it running and go out for testing and drive. Since this build has very small budget it has been good trip for learning and also learning manufacturing stuff by myself. I have already ideas what to make different for the next build when the time comes.
I have dedicated page for this build on facebook with lots of photos: https://www.facebook.com/Kingdieselracing and youtube channel https://www.youtube.com/bigdiffas