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    • Diagrams and technical details/specifications of Audi's new 3.0 TFSI twin scroll top mount turbo V6 going into the 2017 B9 Audi S4 and S5

      With the new B9 Audi S5 the most exciting part is not the styling but what is under the hood. The 3.0 TFSI turbo V6 is a new design and also shared with the B9 S4 model. Finding information on this motor is difficult as Audi has not shared much information on the engine themselves.


      Even what Audi did release is not entirely coherent. For example, Audi offers conflicting information on the torque the motor produces:

      Quote Originally Posted by Audi
      From its 2,995 cc of displacement, the V6 TFSI engine with 260 kW (354 hp) produces 15 kW (21 hp) more than the engine in the previous model. It transfers 500 Nm(516.3 lb‑ft) of torque (60 Nm (44.3 lb‑ft) more)
      Quote Originally Posted by Audi
      The 3.0 TFSI engine delivers 260 kW (354 hp) of power with 500 Nm (368.8 lb-ft)of torque.

      Three Audi sources and three different torque figures. Obviously, 516.3 lb-ft is a mistake so we can throw that out as 500 newton-meters is 368 lb-ft and that is the correct figure.

      For whatever reason, Audi's technical video states torque is 398 lb-ft. That may be an indication the torque is underrated or of an overboost feature. Considering Audi decided to mate the 3.0 TFSI Turbo to an 8-speed automatic we're guessing the torque increase is pretty significant and Audi sandbagging 400 lb-ft or more is probably well within reason.


      What is the most exciting technical development of this engine? The twin scroll turbocharger. It is mounted up top in the valley of the V6. Why did they design it this way? Well, Audi explains it well here:

      Quote Originally Posted by Audi
      The turbocharger, which replaces the mechanical supercharger of the previous engine, operates according to the twin scroll principle. The exhaust branches of the two cylinder banks run separately in both the exhaust manifold and turbocharger housing, and they do not merge until just before the turbine wheel. This technology avoids undesirable interactions between the two gas streams, and it makes a large contribution toward early and strong torque build-up.

      The turbocharger is placed inside the 90-degree V of the cylinder banks instead of the usual location outside next to the crankcase. Accordingly, the exhaust side is on the inner side of the cylinder heads and the intake side on the outer side. This layout enables compact construction and short gas flow paths with minimal flow losses – as a result, the 3.0 V6 TFSI responds extremely spontaneously and directly.
      Because they mounted it up top in the valley they can easily get both banks of exhaust gases to the turbo. There is no need for a ton of cross manifold piping and the design makes sense. The turbocharger benefits from exhaust pulses from both banks and they merge just before the compressor:


      This should make for quick spool and great top end punch as the turbo is continuously fed. Simply a great application of twin scroll turbocharger technology.

      It also should pay dividends with aftermarket tuning as for one you only need to modify a single turbocharger. Audi already placed it in an area that is easy to reach. In theory going to a large single turbocharger is now far easier than it ever was in any previous Audi model. The holdup will be the software tuning as always with the Germans.

      Not only is the engine more powerful than the supercharged motor it replaces it also weighs less:

      Quote Originally Posted by Audi
      A fundamental redesign of the V6 TFSI has lowered its weight by 14 kg (30.9 lb) to 172 kg (379.2 lb). The crankcase, which is produced from an aluminum alloy in a complex sand-casting process, integrates thin-walled gray cast iron cylinder liners. This reduces friction in interplay with newly developed rings for the aluminum pistons.
      Plus they improved the cooling system:

      Quote Originally Posted by Audi
      Another key efficiency component is thermal management. The crankcase and cylinder head have separate coolant circulation loops. After a cold start, the switchable water pump controls the flow of coolant through the engine to bring the oil up to its operating temperature quickly. The exhaust manifold is integrated in the cylinder head, and coolant is circulated around it, which helps to warm up the engine quickly. When the engine is warm, the system reduces the exhaust gas temperature, which in turn reduces fuel consumption, especially when driving in a sporty style.

      A lighter motor with superior cooling? That sounds great to us especially those of us who intend to raise boost.


      Audi also raises the compression ratio. How much? They don't say. It is higher than the 3.0 TFSI it replaces so we know it is more than 10.3:1. It is safe to guess they push it to around 11.0:1. BMW runs 11.1:1 in their new turbo B58 motor which will compete with the Audi 3.0 TFSI.

      Audi states they achieve a compression ratio bump without any issues due to their valvelift system:

      Quote Originally Posted by Audi
      The key factor in successfully attaining efficiency is the new combustion method that originated in the V6 3.0 TFSI from Audi. It is based on what is known as the B-cycle, which is similar to the process used in the Audi A4 2.0 TFSI with 140 kW (190 hp)* and utilizes the high-pressure injection valves that are arranged centrally in the combustion chambers.

      In the V6 TFSI as well, the shortened compression phase of the further developed combustion method enables an engine process with a significantly elevated geometric compression ratio. Efficiency benefits have been achieved in combination with a normal expansion phase that is longer than the compression phase, improving the engine’s efficiency.

      Normally, this type of modification would result in significantly reduced chamber filling, and the high compression would increase the tendency to engine knock that would significantly reduce the attainable power. However, the Audi valvelift system resolves the conflict between efficiency and power goals. In the part-load region, it enables very short intake valve opening times of 130 crankshaft degrees while simultaneously closing the intake valves early. At higher loads, the inlet valves can be shifted over to a camshaft contour with a longer opening time and larger valve stroke that maximizes engine power.
      We have a twin scroll turbo in a high compression V6. Audi is definitely making what will be a very responsive turbo V6. Their emphasis seems to be on eliminating lag as well as creating a very efficient design.

      We wish we had more technical specs. Additionally, is this the engine based on the new Porsche top mount V8 as that V8 is going to provide the basis for the next generation RS4/RS5 V6 Turbo engine?

      If we had the bore and stroke figures we could tell you now. Audi states this new 3.0 TFSI Turbo V6 engine is 2995 cc's.

      Quote Originally Posted by Audi
      From its 2,995 cc of displacement, the V6 TFSI engine
      That means the bore and stroke are not 86x86mm as in the new Porsche V8. Displacement would be 2997.3 cc with 86x86mm. If you plug in the bore and stroke from the supercharged 3.0 TFSI motor at 84.5x89mm it results in 2994.6 cc. It rounds up nicely to 2995 cc.

      What does this tell us? That this new engine is not exactly a completely ground up design as Audi claims. It also tells us that this motor will not serve as the base engine platform for the B9 RS4 and RS5 but it will be the new V6 based on the new Porsche V8. That is of course providing that Audi did not make any more mistakes in their press releases.

      Either way this will be a very exciting tuner platform and it is mated to a stout 8-speed ZF 8HP automatic which sees duty in the RS7 which is a far heavier car and its 4.0 TFSI V8 produces more torque out of the box. Tuned RS7's are holding together which means the transmission in the B9 S4 and S5 it should be good for 650 lb-ft of torque if not more. ZF themselves claims they have variants good for 737 lb-ft torque but there is no way of knowing yet which variant the S4 and S5 will get. For reference, the RS6 and RS7 utilize the ZF 8HP70.

      Audi has a great design here and on paper it certainly seems better than its competition. We'll know more when Audi tells us more.








      This article was originally published in forum thread: Diagrams and technical details/specifications of Audi's new 3.0 TFSI twin scroll top mount turbo V6 going into the 2017 B9 Audi S4 and S5 started by Sticky View original post
      Comments 22 Comments
      1. spool twice's Avatar
        spool twice -
        the only downside I see, they kept the timing chain drive system at the back of the motor. We all know that timing chain systems aren't entirely fool proof, and its a 21 hour job. Otherwise, I can't wait to start tinkering with it once I get my hands on it. It's also turbo'd, which hopefully could mean the introduction of COBB or BMS on the B9 platform (cross my fingers!)
      1. Stevenh's Avatar
        Stevenh -
        Interesting design. It looks like the head and exhaust manifold are a single casting. Hopefully, if there is nothing goofy going on, that turbo could be a 4 or 5 hour r&r with jack stands and hand tools.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by spool twice Click here to enlarge
        It's also turbo'd, which hopefully could mean the introduction of COBB or BMS on the B9 platform (cross my fingers!)
        Hmmm... BMS is already doing some VAG stuff so maybe they would be inclined to tackle an Audi? Worth asking @Terry@BMS about it.

        I kind of want one of these just for fun now. All wheel drive, four door, auto, nice single turbo up top, what's not to like?

        I think this engine design is far more impressive than the S55 personally.
      1. SpeedLimit?'s Avatar
        SpeedLimit? -
        Im surprised that Audi didn't play up to the fact that they used the inverted head v6 turbo design in their lemans program in the past. Looking forward to seeing how it performs.
      1. kouzman's Avatar
        kouzman -
        I am already envisioning a big 74mm between the V!

        changes are that this engine is the one that the small R8 will get and its a good idea that other models will start using it first.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by kouzman Click here to enlarge
        changes are that this engine is the one that the small R8 will get and its a good idea that other models will start using it first.
        Maybe but I don't think so. The better bet for the R8 is the RS4/RS5 twin turbo V6.
      1. kouzman's Avatar
        kouzman -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Maybe but I don't think so. The better bet for the R8 is the RS4/RS5 twin turbo V6.

        you maybe right. they might use the common v6 that is commonly being developed with Porsche.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by kouzman Click here to enlarge
        you maybe right. they might use the common v6 that is commonly being developed with Porsche.
        I just think it makes more sense because the R8 previously used the RS4 motor and that will be the new RS4 motor. Plus, the R8 will come with more than 354 horsepower so it's the most logical choice.

        I don't know for sure it's just what make sense to me.
      1. Enfiftyfore's Avatar
        Enfiftyfore -
        Goodluck aftermarket developers making manifolds, holy cow.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by Enfiftyfore Click here to enlarge
        Goodluck aftermarket developers making manifolds, holy cow.
        It will separate the men from the boys.
      1. George Smooth's Avatar
        George Smooth -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Hmmm... BMS is already doing some VAG stuff so maybe they would be inclined to tackle an Audi? Worth asking @Terry@BMS about it.

        I kind of want one of these just for fun now. All wheel drive, four door, auto, nice single turbo up top, what's not to like?

        I think this engine design is far more impressive than the S55 personally.
        The S4 is planned at least for a Stage 1 tuner.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by George Smooth Click here to enlarge
        The S4 is planned at least for a Stage 1 tuner.
        Oh is that so?
      1. George Smooth's Avatar
        George Smooth -
        What is interesting to note from the engine diagrams is they are using a pneumatic waist gate and not electric.
      1. 93siro's Avatar
        93siro -
        The VM motori diesel v6 is also single turbo between the vee.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by 93siro Click here to enlarge
        The VM motori diesel v6 is also single turbo between the vee.
        What motor are you referring to?
      1. 93siro's Avatar
        93siro -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        What motor are you referring to?
        The diesel in Jeep.

        I mixed the threads i was replying to someone in another thread. :FACEPALM:
      1. Bowser330's Avatar
        Bowser330 -
        I have a feeling the Audi's that will get this new V6T will be getting the ZF 8HP50 (500nm) 369ftlbs.

        The ZF 8HP50 should be the gearbox in the BMW _40i range as well...

        http://youwheel.com/home/2016/01/24/...2016-bmw-340i/
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by Bowser330 Click here to enlarge
        I have a feeling the Audi's that will get this new V6T will be getting the ZF 8HP50 (500nm) 369ftlbs.
        369 lb-ft? That doesn't sound right.
      1. Bowser330's Avatar
        Bowser330 -
        Trust me I want it to be the 8hp70 as much as the next guy but I just don't expect it to happen...

        I don't think they have a model between the new 50 and the 70 or newer 75....so wouldn't 516 lbft (700nm) or 553lbft (750nm) be a bit overkill? What's their incentive for providing such an overbuilt transmission in a 3.0 v6T?
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by Bowser330 Click here to enlarge
        What's their incentive for providing such an overbuilt transmission in a 3.0 v6T?
        That they know it will hold the torque as people will tune? Also, if they are buying these transmissions it might lower the cost to order many of them knowing they are going in multiple models.

        I hope they go with the stout box but I guess we'll find out.