Rumormill: BMW looking at triple-turbo diesel for new performance X5
BMW X5 M – Click above for high-res image gallery
According to a post on the forums at GermanCarZone, BMW is currently working on a new version of its 3.0-liter six-cylinder diesel engine, which puts out 286 horsepower and 413 lb-ft of torque in its current, twin-turbocharged guise. To bump that power peak a bit higher, those crazy German engineers are rumored to be adding a third turbocharger that would boost horsepower to around 350.
This new tri-turbo diesel V6 would see its first application in a BMW X5 Performance Diesel. In a bid to maintain the oil-burners fuel efficiency, BMW would add hybrid componentry that includes stop/start and regenerative braking. These bits would earn the big SUV entrance into the automaker's Efficient Dynamics club.
In addition to the high-performance engine, the X5 Performance Diesel would reportedly get a unique body kit that includes subtle lips around the wheel arches along with revised air intakes and a front spoiler. It's too early to verify any of these rumors, but we'll be sure to keep our ears to the ground for more.
Gallery: BMW X6 M
[Source: GermanCarZone via BMWBlog]
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Reader Comments (Page 1 of 2)
LimeDaiquiri 2:34PM (4/10/2009)
Three turbos?
Hmm. Haven't seen that in a while...
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why not the LS2LS7? 7:42PM (4/10/2009)
Mercedes did it on a show car too. It's called the tri-turbo.
Steven 2:35PM (4/10/2009)
That front bumper looks like a cheap, tasteless aftermarket piece.
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Aloysius Vampa 2:35PM (4/10/2009)
V6?
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Jay 3:14PM (4/10/2009)
No, Straight 6. That's how they can use 3 turbos easily.
Aloysius Vampa 6:21PM (4/10/2009)
I know it's an straight 6. But does Mr. Korzeniewski?
roadkillrob 8:32AM (4/11/2009)
Seems like 50% of autoblog writers think BMW's use V6's - someone on here posts an article every few months about the BMW V6 - makes you wonder how many other facts are incorrect when they screw up the most obvious things!
Nick Vrana 2:42PM (4/10/2009)
interesting design choice, instead of inducing more lag by replacing the turbos, they are adding a single big one behind the two little ones for top end airflow. I like it.
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Thetruck454 2:55PM (4/10/2009)
I am a big fan... that is one of the biggest drawbacks of going for more boost
Colin 3:38PM (4/10/2009)
It's a straight six for sure, I've notice that autoblog has made that mistake a few times in the past.
Luis 2:48PM (4/10/2009)
There's no V's in their sixes!
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Steven 2:53PM (4/10/2009)
I'm guessing they'll call it BMW X5 XdriveD3 M
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Steven 2:54PM (4/10/2009)
Unfunny
Steven 2:56PM (4/10/2009)
Talk to yourself much?
Franz 2:57PM (4/10/2009)
I doubt it'll be a V6. I don't see BMW abandoning it's straight six anytime soon.
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BoxerFanatic 2:59PM (4/10/2009)
Three turbos?
How many compressors and turbines do they need before they just decide to put a turboshaft jet engine in the thing?
Honestly... with that much hardware, why not just make it one big turbo with a combustion stage, and make that the powerplant, rather than just making three small turbos support a piston engine.
Some turbines can burn diesel, kerosene, ethanol, methanol, or just about any fairly un-contaminated organic liquid as a fuel.
And the front end of this, as well as the WHOLE X6-M, is ugly as hell.
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Dan 3:16PM (4/10/2009)
Study up on Chrysler turbine cars and the M1 Abrams, then give us a breif report next class period.
MikeW 3:20PM (4/10/2009)
Mercedes had that concept with 3 turbos on a V6, two small outside the Vee bank, and a larger one in the Vee.
So for a performance BMW this makes sense. Use two large ones for top end diesel power 2500-5000rpm
and a small one for low speed operation. Basically expanding the current serial-sequential setup.
BoxerFanatic 3:54PM (4/10/2009)
I have looked into those.
And I have proposed solutions to the two distinct problems.
1: throttle response... Disconnect the turbine speed from the ground speed. The Abrams does it with hydraulic drive. I suggested electric drive, with just enough battery/capacitance to pick up the slack between the two, and to keep the turbine at generally smooth engine speed, or at least smooth changes. Electric drive would also have the benefit of regenerative braking.
2: exhaust heat... the other big problem with the chrysler turbine cars... A bypass system could be devised to flow compressed air around the combustion and turbine stages, to diffuse the hot exhaust. Not only that, but the more efficient the turbine stage, the more kinetic energy it pulls from the combustion heat and pressure, and the exhaust, which is not used for thrust, will be cooler than older jet turbine technology.
The Abrams and others use centrifugal compressors (which is basically the compressor side of a turbocharger), most jet engines use axial compressors (fan blades like an enclosed multi-blade airscrew.
If you combine the two, as Pratt&Whitney have, they have a hybrid axial first stage, and centrifugal second stage compressor, often called diagonal flow compressor.... which could be very good if scaled down from VLJ, to automotive size (and scaled for near-steady-state electric generation, not outright kinetic drive to the pavement which would require higher power spikes, and a larger engine capacity than ideal for steady-state)
With an instant-torque throttle response of electric drive, with recouperative-energy braking (drive motors become generators when coasting-down and braking.)
The benefits of liquid fuel and internal combustion on board (high energy density, fast liquid fillup, burns any organic liquid fuel)
minimal or modest electric capacity (less battery weight, charged on board, not by plug-in to a power grid, unless you really must.)
Minimum exhaust heat by air-to-air exhaust diffusion (and clean exhaust due to full burn characteristics of the combustion stage, and much less load than an aircraft)
Where exactly are the down-sides?
Tech has come a LONG, LONG way since the '60s turbine cars, which were mechanical/hydraulic drive, IIRC... and a lot less load and power demand than a main battle tank or a locomotive... the turbine can be small. Possibly smaller than a piston engine, or roughly the size of a rotary, maybe just a little bigger...
With mass-market economies of scale, and less catastrophic failure precautions and cost expense than the aircraft industries (cars don't fall out of the sky if something goes wrong...) just like automotive piston engines aren't as meticulous as piston engines for aircraft, the drivetrains may start out expensive, but would quickly come down in price as R&D happens.
Is that enough of a report?
RWD 7:18PM (4/11/2009)
@Boxer: A+ work. I absolutely agree and have thought about this for some time.
But at that point, why not have the car completely powered by an electric motor/batteries which get electricity from a small turbine which spins up as needed? A turbine just large enough so that at it's max RPM it's enough to keep the batteries going at the car's full throttle. No direct link between the turbine and the drivetrain... Although that maybe what you were getting at :)
A diesel turbine hybrid anyone? I can't imagine a more efficient way to make oil power an automobile.