>> A car made by Toyota that has much lower CO2 output than most other 
>> American cars :-)
>
> ...but Toyota is Japanese...?

They sell a lot in America though.

> More importantly, I gather that most American cars are horrifyingly 
> inefficient, so beating that shouldn't be too hard I'd guess. I don't 
> really know.

I think that's why they sell a lot.  The issue in Europe is that you can 
just go and buy a small efficient diesel car for half the price of the Prius 
and it will have similar CO2 and mpg.  So there isn't any reason to get a 
Prius.

Post a reply to this message

scott wrote:
>>> A car made by Toyota that has much lower CO2 output than most other 
>>> American cars :-)
>>
>> ...but Toyota is Japanese...?
> 
> They sell a lot in America though.

Ah, OK.

>> More importantly, I gather that most American cars are horrifyingly 
>> inefficient, so beating that shouldn't be too hard I'd guess. I don't 
>> really know.
> 
> I think that's why they sell a lot.

Really?

> The issue in Europe is that you can 
> just go and buy a small efficient diesel car for half the price of the 
> Prius and it will have similar CO2 and mpg.  So there isn't any reason 
> to get a Prius.

Oh, I see. I thought you meant that American cars sell well because 
they're horrifyingly inefficient! :-D

Post a reply to this message

Invisible wrote:
> Interesting fact: In elliptic geometry, pi is less than arcsine 1.

It's less than arcsine 1 where you're sitting right now. That's why they say 
gravity bends space-time.

-- 
Darren New, San Diego CA, USA (PST)
   Forget "focus follows mouse." When do
   I get "focus follows gaze"?

Post a reply to this message

Invisible wrote:
> ...but Toyota is Japanese...?

Toyota is *originally* japanese. Like any giant manufacturing company in 
industries heavily tariffed, they have plants all over the world, including 
the USA.

> More importantly, I gather that most American cars are horrifyingly 
> inefficient, 

Not especially. They're *bigger* than what you find in downtown london, for 
the most part, but the Prius gets something like 40+MPG while still holding 
four people plus a bit of luggage.

-- 
Darren New, San Diego CA, USA (PST)
   Forget "focus follows mouse." When do
   I get "focus follows gaze"?

Post a reply to this message

>> More importantly, I gather that most American cars are horrifyingly 
>> inefficient, 
> 
> Not especially. They're *bigger* than what you find in downtown london, 
> for the most part, but the Prius gets something like 40+MPG while still 
> holding four people plus a bit of luggage.

Heck, my Renault Megan holds 5 people and gets roughly 45 MPG.

[Or rather, it did until recently... I haven't figured out why it's 
suddenly started rapidly decreasing.]

Post a reply to this message

> but the Prius gets something like 40+MPG while still holding four people 
> plus a bit of luggage.

Cars that get 40+ American MPG (48 UK MPG, 5.9 litres / 100 km) while 
holding 5 people and luggage are normal here in Europe - plus they're faster 
than the Prius.

One word.  Diesel.

Post a reply to this message

> Cars that get 40+ American MPG (48 UK MPG, 5.9 litres / 100 km) while 
> holding 5 people and luggage are normal here in Europe

If Top Gear is to be believed, American cars also can't corner.

> One word.  Diesel.

...

Post a reply to this message

> Heck, my Renault Megan holds 5 people and gets roughly 45 MPG.

My car too holds 5 people plus luggage, gets 55 MPG (if I don't go too fast 
on the autobahn!), plus seems to be way faster than a Prius (3 seconds 
faster to 60 mph, and 30 mph faster top speed).  It's nothing special.

BTW UK MPGs are different to American ones.  40 American MPG = 48 UK MPG

Post a reply to this message

Invisible wrote:
> http://www.xkcd.com/687/
> 
> Interesting fact: In elliptic geometry, pi is less than arcsine 1. In 
> hyperbolic geometry, it's more than arcsine 1.

I don't think this is true -- pi is defined in Euclidean space.  Read 
the first sentence of the Wikipedia article on it.

Post a reply to this message

scott wrote:
> 
> Cars that get 40+ American MPG (48 UK MPG, 5.9 litres / 100 km) while
> holding 5 people and luggage are normal here in Europe - plus they're
> faster than the Prius.

I'll be waiting over 42 American MPG with just enough room for 5 people
and some luggage (OTOH most of the time just me, secondarily me and
Sonic) - even with the warming needed at winter - still having
150bhp/320Nm (upgradeable to 175bhp/370Nm with just a software) with
pretty decent equipment. Sure, it'll be one of the last of it's kind,
but I'm still sure it'll give a good ride for the next 5 years (roughly
300Mm's). Can't wait for next week :).

> One word.  Diesel.

Yep. I ordered a Saab 9-3 SC Vector TiDS. Got something like 7ke off
from retail price, since the car is MY09, manufactured just to keep the
factory running while guessing the future.

-Aero

Post a reply to this message

Invisible wrote:
> Heck, my Renault Megan holds 5 people and gets roughly 45 MPG.

OK, I misremembered. The official numbers are about 50MPG for the Prius, and 
that's not even driving conservatively. In contrast, the same measurements 
show the "smart twofour coupe" gets about 33 to 40 MPG.

The Megane seems to be a diesel car, which tends to get better mileage 
anyway, and almost as good as a Prius running on gasoline.

-- 
Darren New, San Diego CA, USA (PST)
   Forget "focus follows mouse." When do
   I get "focus follows gaze"?

Post a reply to this message

Kevin Wampler <wam### [at] uwashingtonedu> wrote:
> Invisible wrote:
> > http://www.xkcd.com/687/
> > 
> > Interesting fact: In elliptic geometry, pi is less than arcsine 1. In 
> > hyperbolic geometry, it's more than arcsine 1.

> I don't think this is true -- pi is defined in Euclidean space.  Read 
> the first sentence of the Wikipedia article on it.

  Yeah. You can't say "pi is xyz" where xyz is something else than 3.1415...
because pi is *defined* as a *constant*, and constants don't change depending
on the situation. The definition of pi implies euclidean geometry.

-- 
                                                          - Warp

Post a reply to this message

Eero Ahonen wrote:

>  - still having
> 150bhp/320Nm (upgradeable to 175bhp/370Nm with just a software) with

Let’s have an argument about the difference between hp and bhp, please. :-P

-- 

Best Regards,
	Stephen

Post a reply to this message

Warp wrote:
> Kevin Wampler <wam### [at] uwashingtonedu> wrote:
>> Invisible wrote:
>>> http://www.xkcd.com/687/
>>>
>>> Interesting fact: In elliptic geometry, pi is less than arcsine 1. In 
>>> hyperbolic geometry, it's more than arcsine 1.
> 
>> I don't think this is true -- pi is defined in Euclidean space.  Read 
>> the first sentence of the Wikipedia article on it.
> 
>   Yeah. You can't say "pi is xyz" where xyz is something else than 3.1415...
> because pi is *defined* as a *constant*, and constants don't change depending
> on the situation. The definition of pi implies euclidean geometry.
> 

What about xyz = the ratio of any circle's circumference to its diameter?


-- 

Best Regards,
	Stephen

Post a reply to this message

>> Interesting fact: In elliptic geometry, pi is less than arcsine 1. In 
>> hyperbolic geometry, it's more than arcsine 1.
> 
> I don't think this is true -- pi is defined in Euclidean space.

OK, I rephrase: In non-Euclidian space, the ratio of a circle's 
circumfirance to its diameter can be made arbitrarily large or small.

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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Stephen wrote:
> What about xyz = the ratio of any circle's circumference to its diameter?

Define "circle".  Now define "distance".  Now we're getting somewhere.

-- 
Darren New, San Diego CA, USA (PST)
   Forget "focus follows mouse." When do
   I get "focus follows gaze"?

Post a reply to this message

>> What about xyz = the ratio of any circle's circumference to its diameter?
> 
> Define "circle".

The set of all points at distance r from the point c.

> Now define "distance".

I actually can't find a definition for how to do this in a non-Euclidean 
space.

> Now we're getting somewhere.

Well, yes... I'm sure somebody somewhere has long since worked all this 
out in excruciating detail. ;-)

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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Darren New wrote:
> Stephen wrote:
>> What about xyz = the ratio of any circle's circumference to its diameter?
> 
> Define "circle".  Now define "distance".  

Why?

> Now we're getting somewhere.
> 

No we are here ;)

“Here and Now!” Quoth the mynah bird.

-- 

Best Regards,
	Stephen

Post a reply to this message

Stephen <mca### [at] aoldotcom> wrote:
> What about xyz = the ratio of any circle's circumference to its diameter?

  If it's in Euclidean space, then it's pi, else it isn't.

-- 
                                                          - Warp

Post a reply to this message

Warp wrote:
> Stephen <mca### [at] aoldotcom> wrote:
>> What about xyz = the ratio of any circle's circumference to its diameter?
> 
>   If it's in Euclidean space, then it's pi, else it isn't.
> 

Would you run that past me again, in English? :-)

-- 

Best Regards,
	Stephen

Post a reply to this message

Orchid XP v8 wrote:
>>> What about xyz = the ratio of any circle's circumference to its 
>>> diameter?
>>
>> Define "circle".
> 
> The set of all points at distance r from the point c.
> 
>> Now define "distance".
> 
> I actually can't find a definition for how to do this in a non-Euclidean 
> space.

Oh, I forgot. Now you have to also define the length of a curved line with 
no endpoints. :)

> Well, yes... I'm sure somebody somewhere has long since worked all this 
> out in excruciating detail. ;-)

Well, yes.

-- 
Darren New, San Diego CA, USA (PST)
   Forget "focus follows mouse." When do
   I get "focus follows gaze"?

Post a reply to this message

Stephen wrote:
> 
> What about xyz = the ratio of any circle's circumference to its diameter?
> 

The main problem here is that xyz is not a constant, but is rather a 
function.  In spherical and hyperbolic spaces it can be defined as a 
function of the radius so you need to say something like:

xyz(r) = the ratio of the circumference to the diameter of a circle of 
radius r

If your space doesn't have a constant curvature, then it's a function of 
yet more parameters.

The main issue isn't only that pi has a pre-existing meaning, it's that 
the value in these non-euclidean spaces isn't even a constant.

Post a reply to this message

Darren New wrote:
> Now define "distance".

I thought the underlying assumption in this thread was that we're 
dealing spaces equipped with a metric tensor, do you automatically get a 
definition of distance in the standard manner.  How does this require 
extra care to define?

I suppose you could argue that circles are a bit trickier to define, but 
I think the normal one will work well, and should even be well-behaved 
on genus-0 manifolds, or locally on any smooth manifold (like spherical 
or hyperbolic spaces).

Post a reply to this message

Kevin Wampler wrote:
> should even be well-behaved 
> on genus-0 manifolds

I take that back, it's obviously not quite well behaved on a sphere 
(under some definitions of well-behaved) since there are no circles of 
sufficient large radii.

Post a reply to this message

>> should even be well-behaved on genus-0 manifolds
> 
> I take that back, it's obviously not quite well behaved on a sphere 
> (under some definitions of well-behaved) since there are no circles of 
> sufficient large radii.

Any possible line segment in elliptic geometry can be used as a circle 
diammeter. (Since lines that are "too large" to define a circle won't 
fit into the space in the first place.)

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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Kevin Wampler wrote:

> I thought the underlying assumption in this thread was that we're 
> dealing spaces equipped with a metric tensor, do you automatically get a 
> definition of distance in the standard manner.  How does this require 
> extra care to define?
> 
> I suppose you could argue that circles are a bit trickier to define, but 
> I think the normal one will work well, and should even be well-behaved 
> on genus-0 manifolds, or locally on any smooth manifold (like spherical 
> or hyperbolic spaces).

That's a whole crapload of jargon, right there.

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

Orchid XP v8 wrote:
>
> Any possible line segment in elliptic geometry can be used as a circle 
> diammeter. (Since lines that are "too large" to define a circle won't 
> fit into the space in the first place.)
> 

Yes, obviously, so long as you don't define line segments so that a line 
is allowed to overlap with itself.  But I defined xyz as a function of 
the *radius* of a circle, not as a function over line segments. 
Defining circles so that they work for all radii under this definition 
requires a touch more care (although it is possible).

Post a reply to this message

Orchid XP v8 wrote:
> 
> That's a whole crapload of jargon, right there.
> 

Those are all very basic terms for dealing with non-Euclidean spaces. 
Since we're talking about non-Euclidean spaces, I don't think it's 
uncalled for.

That said, you do have something of a point there, so I'll rephrase:

I thought we were assuming that the spaces we were talking about come 
with a pre-defined notion of distance, so why is there a need to 
explicitly define it ourselves?

Post a reply to this message

>> That's a whole crapload of jargon, right there.
> 
> Those are all very basic terms for dealing with non-Euclidean spaces. 
> Since we're talking about non-Euclidean spaces, I don't think it's 
> uncalled for.

Not uncalled for, no. I'm just impressed that there exist people who 
actually know WHAT THE HELL THIS STUFF MEANS!

> That said, you do have something of a point there, so I'll rephrase:
> 
> I thought we were assuming that the spaces we were talking about come 
> with a pre-defined notion of distance, so why is there a need to 
> explicitly define it ourselves?

Yeah, that was basically my assumption too.

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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Kevin Wampler wrote:
> I thought we were assuming that the spaces we were talking about come 
> with a pre-defined notion of distance, so why is there a need to 
> explicitly define it ourselves?

I think I was more making the point that "distance" isn't a simple 
definition when you're talking about space that curves in different 
directions in different places.

Indeed, isn't it possible to have spaces where the distance from here to 
there is different than the distance from there to here?

-- 
Darren New, San Diego CA, USA (PST)
   Forget "focus follows mouse." When do
   I get "focus follows gaze"?

Post a reply to this message

Darren New wrote:

> I think I was more making the point that "distance" isn't a simple 
> definition when you're talking about space that curves in different 
> directions in different places.

Sure. I get that.

> Indeed, isn't it possible to have spaces where the distance from here to 
> there is different than the distance from there to here?

No. The definition of "metric" demands that it is symmetric (and 
reflexive, and transitive).

You can, of course, define a function that represents some sort of 
"nearness" which never the less lacks this property...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

Darren New wrote:
> 
> I think I was more making the point that "distance" isn't a simple 
> definition when you're talking about space that curves in different 
> directions in different places.

I suppose I normally view distance in Euclidean space from the same 
definition that applies to non-Euclidean spaces, rather than the 
sqrt(dx^2 + dy^2) form, so I didn't really consider this.  You're right 
though, if you're starting from the pythorgean theorem view of distance 
it does bear some thinking about how it generalizes to the non-Euclidean 
space.

That said, I'm not sure it's necessary to actually understand the proper 
definition of distance in order to talk about circles in other spaces -- 
particularly if we limit ourselves to spherical and hyperbolic spaces 
which are more or less easy to visualize.

> Indeed, isn't it possible to have spaces where the distance from here to 
> there is different than the distance from there to here?


Sure, but the standard interpretation of "non-Euclidean space" that I'm 
aware, ie "Riemannian manifold", uses a definition of distance which 
doesn't allow such things.  All distances are proper distances in that 
they obey symmetry, the triangle inequality, etc.  I suppose, however, 
that you could argue that "non-Eucliean" should be colloquially taken to 
include pseudo-Riemannian spaces too (so as to incorporate Minkowski 
spaces), but even here you have a pretty nice definition of distance, 
although "circles" become a bit nastier to talk about.

It's possible other people mean different things when they say 
non-Euclidean space though, so I don't want to pretend that it's the 
only way to read that term.  Still, that's what had interpreted to be 
implicit in the conversation.

Post a reply to this message

Orchid XP v8 wrote:
> 
> and transitive
> 

I don't think that's what you intended to say.  You probably meant to 
say "triangle inequality".

Post a reply to this message

>> and transitive
> 
> I don't think that's what you intended to say.  You probably meant to 
> say "triangle inequality".

Actually I meant that d(x,y)=0 implies x=y, but even so, that's not the 
right term...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

Post a reply to this message

Orchid XP v8 wrote:
>>> What about xyz = the ratio of any circle's circumference to its
>>> diameter?
>>
>> Define "circle".
> 
> The set of all points at distance r from the point c.
> 

In how many dimensions? Imaginary or real?

Post a reply to this message

On Tue, 12 Jan 2010 11:09:05 +0000, Invisible wrote:

> ...but Toyota is Japanese...?
> 
> More importantly, I gather that most American cars are horrifyingly
> inefficient, so beating that shouldn't be too hard I'd guess. I don't
> really know.

Not much worse than cars in the UK, remember that the US gallon is 
smaller, so 34 MPG here (which is about what I get out of my 10 year old 
Saturn coupe) is about 7 L/100 KM (or about 40 MPG in UK Gallons if I've 
done my math correctly).

The Prius owners I know (a couple) typically get 55-65 MPG (in US 
gallons).  That'd be 66-78 MPG in UK gallons.

Jim

Post a reply to this message

Orchid XP v8 wrote:
>>> and transitive
>>
>> I don't think that's what you intended to say.  You probably meant to 
>> say "triangle inequality".
> 
> Actually I meant that d(x,y)=0 implies x=y, but even so, that's not the 
> right term...

"identity of indiscernibles" is the phrase you want.  And at any rate, 
that conflicts more with your use of the term "reflexive", rather than 
"transitive".  But hey, you got "symmetric"! (and the gist of the 
others, I'm just pulling your leg).

Post a reply to this message

Kevin Wampler wrote:
> Stephen wrote:
>>
>> What about xyz = the ratio of any circle's circumference to its diameter?
>>
> 
> The main problem here is that xyz is not a constant, but is rather a 
> function.  In spherical and hyperbolic spaces it can be defined as a 
> function of the radius so you need to say something like:
> 
> xyz(r) = the ratio of the circumference to the diameter of a circle of 
> radius r
> 
> If your space doesn't have a constant curvature, then it's a function of 
> yet more parameters.
> 
> The main issue isn't only that pi has a pre-existing meaning, it's that 
> the value in these non-euclidean spaces isn't even a constant.

Too much information.
La la la la la. ;)

-- 

Best Regards,
	Stephen

Post a reply to this message

> I'll be waiting over 42 American MPG with just enough room for 5 people
> and some luggage (OTOH most of the time just me, secondarily me and
> Sonic) - even with the warming needed at winter - still having
> 150bhp/320Nm (upgradeable to 175bhp/370Nm with just a software) with
> pretty decent equipment.

Aren't all cars upgradeable with just software nowadays?  In my car the 
"1.6L", "1.8L", "2.0L" and "2.3L" versions all actually have exactly the 
same engine.  You are just choosing whether you want the 116, 143, 177 or 
204 BHP software installed when you buy it :-)  I heard some people got up 
to 265 BHP out of that engine, but to me that seems really stupid as all the 
other components will not have been reliability tested at that power level.

Post a reply to this message

Darren New wrote:

> The Megane seems to be a diesel car, which tends to get better mileage 
> anyway, and almost as good as a Prius running on gasoline.

My Megane is petrol, although I gather there is a diesel version of most 
of these cars now. And yes, diesel has completely different performance 
characteristics.

Post a reply to this message

scott wrote:

> Aren't all cars upgradeable with just software nowadays?  In my car the 
> "1.6L", "1.8L", "2.0L" and "2.3L" versions all actually have exactly the 
> same engine.  You are just choosing whether you want the 116, 143, 177 
> or 204 BHP software installed when you buy it :-)

Erm... 1.6L means that the engine block has a displacement of 1.6L, 
while 2.3L means that the displacement is 2.3L - i.e., the cylinders are 
physically bigger.

The Real WTF of course is that displacement is not directly related to 
power output in the first place...

Post a reply to this message

Stephen wrote:

> Would you run that past me again, in English? :-)

Post a reply to this message

Attachments:
Download 'milnerhindley.png' (78 KB)

Preview of image 'milnerhindley.png'

Invisible wrote:
> Stephen wrote:
> 
>> Would you run that past me again, in English? :-)
> 
> 
> ------------------------------------------------------------------------
> 

The bit where it says take away the number you first thought of.

Nice one BTW :D


-- 

Best Regards,
	Stephen

Post a reply to this message

Stephen wrote:

> Nice one BTW :D

Heh. Somebody had this printed on a T-shirt [as you can probably tell]. 
I just copied the image file. ;-)

That's apparently the Milner-Hindley type inference algorithm. But whatever.

Post a reply to this message

Invisible wrote:
> Stephen wrote:
> 
>> Nice one BTW :D
> 
> Heh. Somebody had this printed on a T-shirt [as you can probably tell]. 
> I just copied the image file. ;-)
> 
> That's apparently the Milner-Hindley type inference algorithm. But 
> whatever.

That's what the file name says :D

-- 

Best Regards,
	Stephen

Post a reply to this message

>> That's apparently the Milner-Hindley type inference algorithm. But 
>> whatever.
> 
> That's what the file name says :D

I believe the correct response is "that's what SHE said!"

And besides, I named the file. (The website does some JavaScript 
trickery to make it maximally awkward to copy the image file. But they 
didn't bargin for the PrtSrc key...)

Post a reply to this message

Kevin Wampler wrote:

> I suppose I normally view distance in Euclidean space from the same 
> definition that applies to non-Euclidean spaces, rather than the 
> sqrt(dx^2 + dy^2) form, so I didn't really consider this.  You're right 
> though, if you're starting from the pythorgean theorem view of distance 
> it does bear some thinking about how it generalizes to the non-Euclidean 
> space.
> 
> That said, I'm not sure it's necessary to actually understand the proper 
> definition of distance in order to talk about circles in other spaces -- 
> particularly if we limit ourselves to spherical and hyperbolic spaces 
> which are more or less easy to visualize.

So how *do* you compute the distance between two points in a non-Euclid 
space anyway?

For that matter, is there a way to unambiguously refer to a specific 
point in such a space?

(Normally you would of course just use Cartesian coordinates, but it is 
not clear to me that this works any more once you remove the parallel 
postulate.)

Post a reply to this message

>> Interesting fact: In elliptic geometry, pi is less than arcsine 1.
> 
> It's less than arcsine 1 where you're sitting right now. That's why they 
> say gravity bends space-time.

Space-time is an inhomogenous space anyway. I hear that gravity bends it 
with positive curvature, but the universe itself appears to have 
slightly negative curvature...

Post a reply to this message

> Erm... 1.6L means that the engine block has a displacement of 1.6L, while 
> 2.3L means that the displacement is 2.3L - i.e., the cylinders are 
> physically bigger.

It used to be like that, if you bought a "one point six" it meant the engine 
displacement was roughly 1600 cc, but nowadays car makers like to keep the 
"one point six" naming convention but actually have a standard engine 
displacement across all models.  A bit like how AMD called their processor 
an XP2400, but it wasn't 2400 MHz.  If I'd bought the "1.6" version of my 
car it would have exactly the same engine as the "2.0" version, displacement 
1998cc.

> The Real WTF of course is that displacement is not directly related to 
> power output in the first place...

There are a vast number of things that significantly affect power output 
apart from displacement.  A useful quantity is "horsepower per litre" to 
compare engines.  Really efficient road-car engines can get up to 100 
HP/litre, racing engines over 300 hp/litre.

Post a reply to this message

scott wrote:
>> Erm... 1.6L means that the engine block has a displacement of 1.6L, 
>> while 2.3L means that the displacement is 2.3L - i.e., the cylinders 
>> are physically bigger.
> 
> It used to be like that, if you bought a "one point six" it meant the 
> engine displacement was roughly 1600 cc, but nowadays car makers like to 
> keep the "one point six" naming convention but actually have a standard 
> engine displacement across all models.  A bit like how AMD called their 
> processor an XP2400, but it wasn't 2400 MHz.  If I'd bought the "1.6" 
> version of my car it would have exactly the same engine as the "2.0" 
> version, displacement 1998cc.

Sure, but AMD don't actually call it the XP 2.4GHz. That would be false 
advertising - as would claiming that an engine has a displacement of X 
when it's actually Y.

>> The Real WTF of course is that displacement is not directly related to 
>> power output in the first place...
> 
> There are a vast number of things that significantly affect power output 
> apart from displacement.  A useful quantity is "horsepower per litre" to 
> compare engines.  Really efficient road-car engines can get up to 100 
> HP/litre, racing engines over 300 hp/litre.

Or just HP if you want to know how powerful it is, MPG if you want to 
know how efficient it is... I never did understand the fascination with 
displacement. (Other than that I guess you can unambiguously measure it.)

Post a reply to this message