>> That 2.7 seconds is a *HUGE* difference. The average acceleration is
>> almost twice as high in the Vaux over the quarter mile.
>
> But the point that keeps getting ignored are the conditions under
> which it does it. Take away the dragstrip tires and the sticky
> dragstrip surface and what does it then become? Weren't the Veyron's
> times on street tires on concrete?
The original question, which I was trying to answer was "While the
Vauxhall obviously would win in a 1/4 mile drag, how much distance do
you think the Veyron would need to pass it assuming both left their foot
in it? 1 mile? 2 miles?", so I simply assumed that this was being run on
an arbitrarily long dragstrip. Anything else throws more unknowns into
the mix and renders the problem entirely unto the realm of supposition,
rather than that of wild extrapolation and randomly chosen googled data.
>> Almost certainly it will be good for over 200mph,
>
> Strictly speculation. We know it's good for I believe they said 183
> (186?) was its trap speed. Whether it can go much faster than this is
> speculation. Not speculation is how much less control he's going to
> have over it at those speeds.
I'm suspect that an optimised dragster will hit the finish line as it
reaches peak power in top gear, however the engine will undoubtedly rev
beyond peak_power_rpm, and so the top speed will be higher than the trap
speed - in a drag race you are interested in
integral(integral(acceleration)) wrt time, i.e. minimising time, rather
than hitting V_max. I don't think that it is unreasonable speculation
to assume that it can run higher speed than the trap speed.
As to stability and control, I'm sure the veyron would be vastly better,
as you say. If I had to pick one to throw down a real road, it'd be the
Veyron, for certain.
> We KNOW the Veyron is good for 253 mph - there's video of it doing it
> and STILL incrementally climbing.
Yup, true.
>> the peak, and it will definitely get there a hell of a lot sooner and
be
>> a hell of a lot further down the road when it does.
>
> Define "a helluva lot".
Lots and lots and lots. I did pretty graphs and everything :-)
> Assuming 1.) they start from a standing start
> as opposed to "they encounter each other driving down the highway and
> have a go at it" 2.) he matches his record time he's 2.7 secs ahead
> at 1/4 mile.
> Except he's not going to since he's going to be on
> street tires on a street surface so we can safely hack off what, at
> least 1.5 secs or so?
> If he's been allowed to put taller gears in it,
> all that will do is reduce his 1/4 mile time even further. Under THOSE
> conditions, how much is he going to be ahead?
I have no idea, but quite a bit. Even limited to 1.5G acceleration, as
it would be on sticky road tyres, the vaux is going to accelerate much
more quickly than the Veyron, because it has about 4 times the
power:weight ratio. By the time the aerodynamics start to play a part,
the Veyron is not accelerating VERY quickly, and will be a reasonable
distance behind, so it will take him a while to catch up. I can't be
any more specific without some hard data..
> Burgerman already related what happened when he had a considerable
> head start on the Veyron. He got trashed at 1.5 miles even though he
> was doing close to 180.
I think that was against a McLaren F1, but yes, the more aerodynamic
vehicle eventually overtook the less aerodynamic one. I think 'trashed'
is a slightly emotive word in the context - at 1.25 miles the McLaren
would have been 'trashed' by the bike?
> And if the Vaux and Veyron were to go at it from a highway speed
> start, how do you figure the Veyron as the underdog?
The BMW M5 can hit 200mph with 500Hp, so lets be conservative and say
that the vaux needs 700Hp to do the same. From aero calcs, the Veyron
needs about 490Hp. The acceleration is given by (engine power-drag
power)/mass, so at 200Mph the vaux has an excess of 1500Hp to accelerate
its ~1000kg, whereas the Veyron has ~500Hp to accelerate its 1700kg - at
200mph the vaux will accelerate 3 times as quickly as the Veyron!
> Have you seen that video of the Veyron vs the Audi R8? If the specs I
> saw are correct, that Audi is a near 190 mph car . They punch it from
> a highway speed start - with the Audi going first. When the Veyron
> floors it, it looks like the Audi slammed the brakes on even though
> he's accelerating, and damn quickly given how fast he's reading off
> the speed 100 - 110 - 120 about as fast as he can say it. Yet by the
> time he hits 120 that Veyron is GONE.
I haven't seen it, but the Audi R8 has 420Hp and weighs 1600kg - the
Veyron should be vastly quicker, especially at high speed.
>> so it will have made rather
>> a significant lead by the time the Veyron matches it's top speed,
>
> Again, which is going to be considerably shortened under street
> conditions. Now who wins in a "drag race" from say 120 to 200?
The vaux, by a country mile.
>> OK, stuff it, lets do the geek thing properly :) I've done a noddy
>> excel drag-race, using the available data for both cars.
> Not familiar with this "noddy" I keep seeing pop up. ?? Please
> translate to American.
Yo, listen up y'all. Noddy was this dude who rocked about in some,
like, totally blinged-out, clockwork wheels down in Toyland.
*ahem* sorry, sorry. 'Noddy' was a series of books for children,
written by Enid Blyton, and is used to mean 'simple' or in my case
'wildly inaccurate by dint of unjustified supposition'.
> Also, what about the phrase "not a lot in it"
> I've seen.
"very close" or "the two things are very similar"
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