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[pic=left]http://www.planet-9.com/gallery/files/6/3/9/gt3hybridnews_z.jpg[/pic] Porsche set to preview a new 911 GT3 R Hybrid race car in Geneva - Following on the announcement a few days ago of the 911 Turbo S, Porsche shocked many journalists and automotive sites with the unveiling of an all new 911 GT3 R Hybrid race car. Our sources at Porsche tell us that the balance of the car is now much more "mid engine like" than a traditional 911 and the mid-mounted flywheel (used instead of a battery and placed where a passenger seat would be) can spin up to 40,000 rpm adding additional gyroscopic benefits. In the hands of Porsche factory race drivers the car achieved better handling results, despite its weight penalty vs. the standard GT3. Another remarkable feature of the car is the "instant boost" capability. In those notoriously furious and fast movies boost was always supplied by Nitrous, in the new GT3 Hybrid the boost is supplied by two electric motors (60kw each) that propel the front wheels giving the car 4 wheel drive capabilities and an additional 160hp for approximately 6-8 seconds at a push of a button on the steering wheel. Need to overtake that Ferrari? Just push the button! (No word from Porsche if there is a limit to how often the button can be pushed or what the typical recharge time is on the flywheel).

Porsche plans to race the car in the 24 hours of Nurburgring on May 15th and campaign an updated version at LeMans as early as 2012. It is interesting to note that just last month Michael Macht had stated that Porsche has no plans for a hybrid 911, we assume he meant in a passenger car, although if the technology proves successful we may be seeing a derivative of this race car on the street sooner rather than later. When asked about the weight distribution, Porsche responded that overall the weight distribution of the GT3 has been much more "equalized" and is on par with a mid-engine car, although Porsche did not reveal exact numbers the representative did go on to say that the center of gravity is lower as well. It isn't like the flat 6 motor out back is any slouch (4.0L and 480HP!) and if Porsche has indeed overcome the weight penalty that the hybrid system adds via a lower center of gravity and improved mid-engine like handling coupled with on-demand all wheel drive, we expect this car to be very competitive if the components are up to the task of endurance racing. Porsche also noted improvements in fuel consumption, meaning fewer pit stops vs. the standard GT3.

Has Porsche killed its own 911 GT3 with dare I say a mid-engine equivalent based on Hybrid technology? It would appear that if racing moves towards hybrids that indeed it will do just that. Even if you don't like this hybrid, there was some additional good news buried in Porsche's discussion of the car, they expect to return to racing at LeMans with a factory backed effort by 2012.

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Re: GT3 Hybrid "Mid Engine" Race Car Unveiled

WOW!!!!
There is so much here to digest.
Anything that moves Porsche's flagship race engineering toward building real mid-engine race cars, is all good to me
 

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Busy little Beavers!
Now this is my kind of hybrid - regenerative power accumulator.
However... if that flywheel self destructed or was involved in a car crash, things could get a bit messy. :eek:
 

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Very interesting. I am interested to see how well it does.
 

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I wonder how big the alternator is? Thinking about the total power management in this car is interesting. And flywheel management. Do you want it at 100% as much as possible to maximize acceleration? Or do you try to manage it at a lower power level to be able to absorb braking energy? I know the writeup says that the front wheel drive boost can be activated by a button on the wheel, but it would make a lot more sense to me to program it in a more integrated manner. I have visions of a power management algorithm tailored for the individual track to not only maximize the performance but maximize the energy efficiency and reducing total fuel consumption. That is, of course, within the limitations of the heat rejection capabilities of the electric motors/generators. That would be FUN to work on.

I'lll tell you one thing, though: you DO NOT want to be in that car if the gyro comes apart.
 

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Two thoughts come to mind. I wonder what advantages the flywheel approach has over a battery or a giant capacitor.

The "gyroscopic effects" ? Since it looks like the flywheel spins on a vertical axis, are they using the gyro precession to counter a roll moment? Since the reaction torque acts at 90 degrees to the roll moment and is also a function of the direction of spin of the flywheel this would result in a pitching moment. Such a moment would be opposite depending if the car was rolling right or rolling left. One way would induce pitching up, the other, down.

Or they could use counter rotating flywheels on the same shaft and eliminate these effects. Very interesting.
 

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Power storage basics.
Efficiency. Gyro; 90-99%. Battery; 80%. Super Cap; 90-99%.
Cost $/kW. Gyro; $. Battery; $$. Super Cap; $$$$$$
Energy transfer rate. Gyro; fast. Battery; v slow. Super Cap; slow.
Lifetime. Gyro; v long. Battery; 500-5k cycles. Super Cap; v long.
Concerns. Gyro; mechanical destruction, explosion. Battery; fire, heat. Super Cap; fire, melting, arcing.

I amazed they can solve the safety issue...assuming it is solved.
 

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Take a look at formular one and from what i could summize from last season is that they have/had quiete a few safety problems.
 

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It seems that calling this "mid engine like" is the first small step in the marketing campaign to move the 911 platform to mid-engine layout. Adding a bunch of weight in the front to equalize the axle weights is nothing like the effect of an actual mid-engine design. Increasing the polar moment iin such a way is quite the opposite, in fact.

As for safety, I don't think this is such a big deal. There are all sorts of turbines spinning around near people with minimal risk (or, at least, with a very good safety record.) Some that come to mind (I'm not suggesting any of these are exacly the same scenarios, just offering them for discussion) are: power turbines at hydro-electric facilities, aircraft turbines (although I never sit on the same plane as the main turbine or prop is spinning,) automotive turbo-chargers and drag race car clutch/flywheels. Heck, even modern 600cc sportbikes spin their crankshafts at 15000 RPM with very few incidents of engine explosions.

I hope this means that we eventually end up with a vast array of mid-engined Porsches from which to choose. Let's see: plain, S, 4, Targa, Turbo, GT3, RS... yeah, life is good!
 

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Ugh! Not a pretty picture!:eek: I imagine they would have to encapsulate it inside some sort of titanium alloy.

Aramid is a much more technically and cost-effective, proven way to contain shrapnel. Containing the energy from a very unlikely flywheel failure is not really much of a technical problem. It will take not much money and more weight than any race driver would want in their car - but so does the whole electric motor/turbine thing. And that body work, cool suit, telemetry, roof, paint ...
 

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The term "red mist" comes to mind... :hilarious:
In the early days of the F-18, we had a turbine wheel failure. The 16 pound wheel broke into 3 pieces. The engine (a test article) had a band of M90 steel about 1/2 inch thick, 5 inches wide secured by 6 high-lock fasteners. One of the pieces hit the band dead center, broke the fasteners, bent the band into essentially a straight radial line, penetrated the center Titanium bulkhead and keel, cut several components, cut a gash in the opposite engine case, then exited the airplane by severing a rib in a manner indicating high velocity impact. Containment is the issue.
 

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Two thoughts come to mind. I wonder what advantages the flywheel approach has over a battery or a giant capacitor.

The "gyroscopic effects" ? Since it looks like the flywheel spins on a vertical axis, are they using the gyro precession to counter a roll moment? Since the reaction torque acts at 90 degrees to the roll moment and is also a function of the direction of spin of the flywheel this would result in a pitching moment. Such a moment would be opposite depending if the car was rolling right or rolling left. One way would induce pitching up, the other, down.

Or they could use counter rotating flywheels on the same shaft and eliminate these effects. Very interesting.
uh....ok....thats just what I was thinking ....;)
 

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Very cool stuff! It will be fun to see how this car does...
 

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Wow. Interesting. The first thing that comes to my mind is...this is Not "mid engine like". As someone said above, this is high-polar-moment of inertia. Granted, better weight distribution, but high polar moment, and higher weight. The mid-engine comparison, sounds like marketing and is a little unsettling. It is way too easy to throw a couple of motors up front and market "mid-engine-like weight distribution". Way easier to add to an existing 911 platform than actually re-packaging the car (and changing it's iconic shape and rear engine placement) to be mid-engine. If the flywheel proved to be impractical for street use, they could always easily throw a few batteries in there too... more weight.

In racing, many things evolve and many outcomes are determined based solely on the rules and whatever advantages are built in for certain layouts. These do not necessarily relate to what is best on the street or in general.

Gyroscopic effects, as someone said above, my thoughts exactly. In racing we want the car to change direction quickly - in any axis. Though, as said, perhaps counter-rotation is being used to minimize this (in my eyes negative) effect.

Flywheel explosions - in the mid 90s I was involved with the Chrysler Patriot WSC (LMP) car effort. I came in near the end and shortly thereafter there was a flywheel explosion on the dyno (not our shop) that killed someone. That pretty much killed the program, along with cyrogenic re-fueling concerns, etc. Of course that was 15 years ago, we were trying to turn too many RPMs, and materials have gotten alot better. I agree Kevlar is a good lightweight tough shield. I'm sure Porsche has sorted the flywheel safety properly, or they wouldn't even be track-testing it.

PDK-only 911 Turbo S-es....and electric motors in the front of this marketed as "mid engine like"....I just hope this all helps them make a lot of money and that they then develop a more powerful Cayman for the more narrowly focused of us. I do applaud them for developing new technology. And, it is a true pleasure being associated with you guys (and gals) - so nice to have so much collective knowledge, and even good manners. Regards.
 

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Two thoughts come to mind. I wonder what advantages the flywheel approach has over a battery or a giant capacitor.

The "gyroscopic effects" ? Since it looks like the flywheel spins on a vertical axis, are they using the gyro precession to counter a roll moment? Since the reaction torque acts at 90 degrees to the roll moment and is also a function of the direction of spin of the flywheel this would result in a pitching moment. Such a moment would be opposite depending if the car was rolling right or rolling left. One way would induce pitching up, the other, down.

Or they could use counter rotating flywheels on the same shaft and eliminate these effects. Very interesting.
Exactly right. Turn one way, it loads the front, turn the other, it loads the rear. Cresting a hill, it will try to roll the car. UNLESS there are two counterrotating rotors. Hmmm. I wonder if you could do that and consider one rotor the stator and the other the rotor. With modrrn-day controls, I'll bet you could do that. Then the reaction forces would counter each other but you would still have the vertical axis stability which would help keep the car flat during turns.
 

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I don't believe the 911 will ever move to a mid engine design. Mid engine feel comes for the better balanced weight distribution. Instant power from the elctro engine without additional stress to the engine is awesome.
 

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Wow. Interesting. The first thing that comes to my mind is...this is Not "mid engine like". As someone said above, this is high-polar-moment of inertia.
Funny you mention "high-polar-moment" this is what the defeinition is on about.com
POLAR MOMENT OF INERTIA

"
Definition: The resistance of an object to rotational acceleration. When the mass of an object is distributed far from its axis of rotation, the object is said to have a high polar moment of inertia. When the mass distribution is close to the axis of rotation, it has a low polar moment of inertia. A mid-engined car has most of its mass within its wheelbase, contributing to a low polar moment of inertia, which, in turn, improves cornering turn-in."


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