Small questions and answers-thread

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Notmi
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Re: Small questions and answers-thread

Postby Notmi » Wed Apr 02, 2008 1:16 pm

PanzerProfile wrote:Ever encountered something like that, Notmi? :mrgreen:

No, luckily :D

Here in Finland, in one city (Tampere) is two competitive hockey teams. And an old finnish joke is that if you go to a bar in Tampere and somebody asks you "Tappara or Ilves" and you answer "Sorry, I don't follow baseball", your popularity is guaranteed ;D
That joke got me ask that question :D
In Australia men are men and sheep are nervous.

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Re: Small questions and answers-thread

Postby Skua » Thu Apr 10, 2008 10:34 am

Michael Emrys wrote:
Skua wrote:What about the two-stage type where both principles are used?


Are they? I admit I never looked into the matter, but I've always assumed that a two stage supercharger was simply two mechanically driven superchargers in sequence. The first raises the air pressure a certain amount and then the second one takes it further. ISTR that the second stage might have a governor that only allows it to be driven (i.e., take power off the crankshaft) above a certain altitude or throttle opening or suchlike.

Michael


Sorry, a case of self-confusion on my part. Thanks for the answers, and those given to PP's were helpful as well. I wonder about one more thing though. Is the compressor more efficient at low revs, because, if I understand it correctly, the turbocarger needs sufficient pressure and therefore more revs before it kicks in?

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Re: Small questions and answers-thread

Postby Notmi » Thu Apr 10, 2008 1:34 pm

Skua wrote:Is the compressor more efficient at low revs, because, if I understand it correctly, the turbocarger needs sufficient pressure and therefore more revs before it kicks in?

True, ithey are more efficient than exhaust powered turbocharger, for the reasons you mentioned: Turbos need sufficient pressure and exhaust volume in order to charge. Thought modern variable geometry turbochargers start working at quite low revs but still not from idle revs as mechanical driven chargers.
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Re: Small questions and answers-thread

Postby Michael Emrys » Fri Apr 11, 2008 4:07 am

I'm not sure that it is more efficient (in fact, the opposite is probably true), but there is less throttle lag.

Michael

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Re: Small questions and answers-thread

Postby Notmi » Fri Apr 11, 2008 5:01 am

Michael Emrys wrote:I'm not sure that it is more efficient (in fact, the opposite is probably true), but there is less throttle lag.

Michael


With low enough revs, turbo isn't charging at all. Therefore, it is inherently inefficient comparing to mechanical charger (at those low revs).
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Re: Small questions and answers-thread

Postby Michael Emrys » Fri Apr 11, 2008 1:03 pm

Notmi wrote:
Michael Emrys wrote:I'm not sure that it is more efficient (in fact, the opposite is probably true), but there is less throttle lag.

Michael


With low enough revs, turbo isn't charging at all. Therefore, it is inherently inefficient comparing to mechanical charger (at those low revs).


But it isn't drawing any power off the engine, therefore more efficient.

;)

Michael

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Re: Small questions and answers-thread

Postby Notmi » Sat Apr 12, 2008 4:52 am

Michael Emrys wrote:But it isn't drawing any power off the engine, therefore more efficient.

;)

Michael

Well, if you want to think about it that way.... :D

But actually, turbos 'draw' a little power off the engine, or prevent them working at their best. This is because they form an obstacle at exhaust manifold and exhaust gases cannot flow freely off the engine, as with non-turbo engine. I admit it is a small fee to pay for all the benefits of turbo. And turbos really give you much, much more power than they 'rob' from engine by blocking free exhaust gas flow.

Hopefully somebody understood what I was saying... :/
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Re: Small questions and answers-thread

Postby Michael Emrys » Sat Apr 12, 2008 7:09 am

Notmi wrote:
Michael Emrys wrote:But it isn't drawing any power off the engine, therefore more efficient.

;)

Michael

Well, if you want to think about it that way.... :D

But actually, turbos 'draw' a little power off the engine, or prevent them working at their best. This is because they form an obstacle at exhaust manifold and exhaust gases cannot flow freely off the engine...


Boy, now we are down to splitting some very fine hairs!

:lol: :lol: :lol:

;)

Michael

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Re: Small questions and answers-thread

Postby Skua » Sat Apr 12, 2008 10:39 am

All right then. Next silly question.

Are kittens ''smarter'' than grown-up cats? It seems that you can learn a two month old kitten a lot of tricks and that it understands quite a lot for having such a small brain. My cat figured out how to open the door to the balcony when it was a kitten, which is not as simple as it sounds. The door has a small lock which locks the handle to the door and he actually figured out that he had to turn the lock, using his teeth, before he could push the door open with the handle. These days he can't even get through an unlocked door without assistance.

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Re: Small questions and answers-thread

Postby Stix » Sat Apr 12, 2008 11:51 am

Most animals and especially mammals appear to be more open minded when young and able to absorb a lot of information.
When growing older this is replaced by habit and routine and possibly the brain gets a bit full.
So yes, in a way young animals are smarter then adults.
As for the specific case of your kitten/cat.... maybe it bumped its head a few times too often and forgot how to do it?
Because common sense, isn't all that common.

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Re: Small questions and answers-thread

Postby PanzerProfile » Sat Apr 12, 2008 8:53 pm

maybe you just need to reset your cat every once in a while. Defragmentation may help as well - gets them to think straight ;)

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Re: Small questions and answers-thread

Postby Stix » Sun Apr 13, 2008 9:23 am

PanzerProfile wrote:Defragmentation may help as well

Are you serious? You fragged your cat? :P
Because common sense, isn't all that common.

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Re: Small questions and answers-thread

Postby Michael Emrys » Sun Apr 13, 2008 11:27 am

I know I was a lot smarter at 19 than I am now at 64...or at least I thought I was.

;)

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Re: Small questions and answers-thread

Postby PanzerProfile » Tue Apr 15, 2008 8:20 pm

Stix wrote:
PanzerProfile wrote:Defragmentation may help as well

Are you serious? You fragged your cat? :P


Yeah, why not? at first, it was brown with black stripes. Now, it's one half brown and one half black :mrgreen: :mrgreen:

No, just kidding ofcourse. Silly, silly man! ;)

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Re: Small questions and answers-thread

Postby Skua » Wed Apr 16, 2008 8:36 am

PanzerProfile wrote:maybe you just need to reset your cat every once in a while. Defragmentation may help as well - gets them to think straight ;)


I follow the the teachings of the great Monty Python and make sure I confuse my cat regularly, so as far as intelectual stimulation goes it is as good as it gets. :mrgreen:


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