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:crazyeyes

You've got to hand it to the Porsche engineers... they're not kidding around.

EDIT: just one thing... I assume you can't generate more than 1G of load on that rig... and in a 1G corner you're actually generating 1.4G total (1G lateral, 1G downward)... so while you can generate the angle of that load (45 degrees), you can't generate that magnitude. Don't know if that makes a significant difference
 

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:crazyeyes

You've got to hand it to the Porsche engineers... they're not kidding around.

EDIT: just one thing... I assume you can't generate more than 1G of load on that rig... and in a 1G corner you're actually generating 1.4G total (1G lateral, 1G downward)... so while you can generate the angle of that load (45 degrees), you can't generate that magnitude. Don't know if that makes a significant difference
I'd think there's a big difference between 1.4G and 1G. And for what Porsche charges for their cars I'd assume they'd run some basic tests like this.
 

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I'd think there's a big difference between 1.4G and 1G. And for what Porsche charges for their cars I'd assume they'd run some basic tests like this.
Oh, yeah... agreed: there's a big difference in forces... but I'm guessing they're trying to determine whether they get sufficient oil pressure regardless of the angle of the forces, not the magnitude. It would be near impossible to design an indoor rig that could generate 1.4G for say, 20 seconds (i.e. a long sweeper), then suddenly go back to 1.0G. Even a centrifugal arm can't change the magnitude of G forces that quickly.
 

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Oh, yeah... agreed: there's a big difference in forces... but I'm guessing they're trying to determine whether they get sufficient oil pressure regardless of the angle of the forces, not the magnitude. It would be near impossible to design an indoor rig that could generate 1.4G for say, 20 seconds (i.e. a long sweeper), then suddenly go back to 1.0G. Even a centrifugal arm can't change the magnitude of G forces that quickly.
I'll certainly agree this test is much better than nothing. And it's kind of silly to compare this to the engineering of the 2ZZ, considering the cost of the cars it was intended for and their low cornering capability.
 

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I don't think the inability to simulate that extra G-force is really important at all. The only thing that additional force does is make the weight of the oil seem higher from the perspective of the pump that's trying to push it up. Not a big deal to just make sure your pump is a strong one.

I think the really important thing they're testing for is to make sure they can slosh it all around without getting any starvation at the pump, without loosing any critical oil flow at important places, without messing up the drainage patterns/flows back to the sump, etc. The important things the rig must simulate are the absolute angles and the fast changes in vectors.

xtn
 

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"basic tests" rotfl
I don't know how you engineer things, but from my standpoint this test is due diligence given the cost and purpose of the car.
 

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Well, since they aren't really testing G forces as I agree with xtn, why don't they just run the engine upside down and then on it's sides for several minutes at high RPM. If the engine can with stand that, it should be go. That's gotta be a safety factor of about 100.:D
 

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Well, since they aren't really testing G forces as I agree with xtn, why don't they just run the engine upside down and then on it's sides for several minutes at high RPM. If the engine can with stand that, it should be go. That's gotta be a safety factor of about 100.:D
That reminds me of the difficulty in designing a piston engine for an aerobatic/combat plane. Talk about random G-vectors! :eek:
 

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The most amazing part of that for me is the size of the hydraulic engine brake to put load on the engine. That sucker is tiny. :eek:

Porsche really does go the extra mile.
+1

There are a lot of cool, fast, innovative sports cars out there...

But the Porsche 911 (in all it's various incarnations) still rules...
 

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the rotation of the motor is simulating what the oil is doing in the motor at certain g loads.i know first had what it does in a sports racer.with much higher g loads.for instance a fast left hand turn would put the oil on the side of the motor and fill the clutch basket(bike engine car)then puke it out the breather.like in the simulation the motor would be rotated completely on its side.
that test rig is very well done to prove what the oil is doing in that motor.
 

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When they started sending men in the space, the NASA designed a 10,000$ pen that could write upside down in zero gravity.

The russians space agency gave their men pencils.
 

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When they started sending men in the space, the NASA designed a 10,000$ pen that could write upside down in zero gravity.

The russians space agency gave their men pencils.
I heard it was grease pencils.
 

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When they started sending men in the space, the NASA designed a 10,000$ pen that could write upside down in zero gravity.

The russians space agency gave their men pencils.
Not at all, although it makes a great urban legend and a way to make fun of "the establishment".

A pen company developed the pen on their own dime (it certainly wasn't a huge technological feat), and since they owned it, they had the rights to advertise their wonderful "Space Pen". People wanted all things "space" at the time, and they sold a LOT of the pens. They provided the pens to the space program.

By the way, a pencil isn't the best thing to use in space (although it would work). The small pieces of graphite that flake off when used would be free to float around in the cabin and possible short circuit electrical components.

And a felt tipped pen works just fine too..


But one thing they did to was attempt to figure out how to make an electric razor that would vacuum up the clippings. They didn't really spend much on it, and didn't get anything that would work very well. But one of the Apollo crews cleverly figured it out. They took a towel, a can of shaving cream, and a safety razor on their trip. Before their re-entry, they shaved and wiped the razor on the towel. I remember the new casters talking about it, and trying to figure out how they came out clean shaved...
 

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Kind of cool. Consider the g-forces and oil flow on an aircraft engine doing acrobatics. That gets interesting.
It's when they do 0 g's that things get interesting. Most engines can handle a lot of negative or positive g's fairly easily, provided they are designed for it, but I think there is a lot of trouble to do sustained zero g flight. But, I have never flown the real acrobatic focused airplanes, which I imagine would deal with zero g flight better than most other aircraft. Oh well, hopefully someone more of an expert than I will chime in.
 
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