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Thursday, 15 August 2013

How Close Are We To 300MPH?


Recently, I learned of a way to make a Bugatti Veyron go 300mph in Gran Turismo 5. For an idea of just how fast that is, the yellow distance markers flashing under the car are at 100m intervals. Of course, you can go 311mph - and much more easily too - if you use the Red Bull X2010/11 prototypes, but this is a road car going 300mph, and that's much more challenging to do than when you have 1600 horsepower, 545kg and a fan sucking you down to the road like the X1s. But it's got me thinking: how long will it take for a real life production car to break the 300mph barrier? For my 300th SBV8 post, I shall ponder this further...

First, the digi-Veyron above. This is a Standard Model car in GT5, so you can't add wings and things to it. If you could, you'd probably add a front splitter, because there's so much front-end lift at 280+ that you need to put a 200kg ballast on the nose to keep it on the ground, and even then there's almost no steering at all! The active rear wing drops down at 230mph to its low-drag setting, and the sudden increase in acceleration is like you've hit a Nitrous Oxide button or something. This is when it stops being a stable car and becomes really very understeer-y indeed. But then, that's why I picked the track with two 11km straights on it. The car has 1256bhp and thanks to the ballast weighs 1624kg despite a Stage 3 Weight Reduction upgrade.

The thing about it is that the standard Veyron in GT5 can't get up to its real life top speed of 253mph. Even on this circuit, it's all done at 248mph. The McLaren F1 is similarly disappointing - the top speed record it held from 1998 to 2004 was 241mph, although that's with a raised rev limiter. Otherwise you're talking around 231mph. In GT5 it won't go far past 220. Why?! That always bugs me. But hey, with more realistic air simulation, this 300mph Veyron could go as fast as 303 or 305mph, couldn't it? Although, if we're talking realism, you're not going to find 200kg to chuck out of the Veyron's 1888kg, because there are so many big oily bits that it needs to top 400km/h reliably and repeatedly (such as nine radiators/intercoolers). Still, with barely more power than a real-world SuperSports, it managed 300.2mph on slick 'Racing' tyres and 298mph on road-spec 'Sports' tyres.

But have any land vehicles done 300mph in reality? Well yes, of course. The first 300mph+ land speed record was in 1937, when on 3rd September, the great speed pioneer Cpt. Malcolm Campbell took one of his iconic Bluebirds - packing a 36.7-litre (!) supercharged Rolls-Royce "R" V12 chucking out 2300bhp (!!) - to Bonneville to set the first outright speed record at the now-famous Salt Flats, at 301.13mph (484.6km/h). Today the fastest car of any kind with an internal combustion engine is called the "Speed Demon Streamliner", which has averaged 439mph over a flying mile and unofficially topped 462mph with a similarly powerful twin-turbo Chrysler "HEMI" V8. But as you can see, like the Bluebird it's no road car!

And so to real-life road cars. You know what else has a bit more power than a Veyron SS and weighs a lot less? The Hennessey Venom GT. If you aren't aware of this car (Steve Tyler has one, you know), what Texan tuner John Hennessey decided on a whim to do was take a Lotus Exige, strip it down to the tub and then build it back up his own way with a long wheelbase, much wider body (as demonstrated where the front wheel arch meets the standard central chassis and sticks out quite far)... and a twelve hundred horsepower Corvette engine. The Twin-Turbo LS7 actually makes 1244bhp, and the car itself weighs somewhere around 1200kg, so we're talking about 1000bhp/tonne here, or nearly twice that of a standard Veyron. The much-hyped Venom has already snatched a couple of acceleration records away from the Koenigsegg Agera R, such as the fastest 0-300km/h (186mph) time, at 13.63 seconds. That's not much longer than it takes my car to hit 60mph! The projected top speed is somewhere around 275mph, which would eclipse the 268mph Veyron SS, but like Koenigsegg and their Agera R (also predicted to do ~275mph), they simply can't find anywhere that would let them find out. Previously VW's Ehra-Lessien test track would've been available - as it was for McLaren - but now they own Bugatti they're not so keen on letting other people go for stratospheric top speeds...

When ShelbySuperCars (no relation to Caroll Shelby) sneaked past the original Veyron with their ugly and childishly-named Ultimate Aero, they used a closed public road in Texas to get their car - which has similar ingredients to the later Venom but not the Exige middle - to 256mph and into the Guinness Book of World Records. Why can't Hennessey pull off the same trick as them? There must be more than one long straight empty road in the vast state of Texas? If all else fails, how about the 90-Mile Straight in Australia?


If you can't hit 275mph in 90 miles, you can't hit 275mph. Simple as. They wouldn't even need all of it, of course. The Veyron needs 5 or so miles, so close 7 or 8 miles of it for a day and go for it!

But what would it take to break 300mph? The Veyron needed an extra 200 horsepower to go another 15mph, so at that rate you'd need about 1600bhp using flawed maths/logic/rounding, but more than that, I don't think the Bug's jellymould shape is really the most aerodynamic, and cutting through the air as cleanly as possible is vital at these speeds, hence why land speed record cars are extremely long, smooth and pointy. So you'd need a low drag coefficient like the VW XL1, which can go 100mph with just 48bhp. But then you also need stability, so you need some downforce, and downforce makes drag. As a case in point and to prove that power's not everything, the Veyron needed 987bhp to break 250mph, but the Koenigsegg CCX (sans TopGear wing) could do 250 with "just" 806bhp, because it was lower and slipperier. Oh, and quite a lot lighter. With less weight to haul around per horsepower, you'll always go faster.

After carefully balancing the aerodynamics (including a small frontal area, i.e. a smaller fist to punch a hole in the air with), you need to make sure that immensely powerful engine won't explode. Ditto the tyres. AND it'll need enough fuel to make it all the way through a top speed run with an unavoidably very thirsty engine running at full blast for a long time.

When it comes to the engine though, the biggest problem will be making it a reasonable road car engine. As I've said before, it's all very well making a heavily-modified 1700bhp Ford GT, but there's no way that thing can go a long time between services or even engine rebuilds, unless you spend most of your time using so little of the engine that the wear and tear is minimal. But if you're going to do that, why buy a ferociously powerful car in the first place?

The answer is most likely for that one time a year when you can really stretch its legs and experience something that a fraction of a percent of cars in the world can do. The PPR Ford GT I linked to can get past 280mph in a standing mile, which is incredible, but how far could it go with five miles? 290? If Bugatti or someone else can engineer a 1600 or 1700bhp car that can be a legit road car, with the right aerodynamics tailored to this kind of speed (the Ford GT was only designed to go 205mph or so), with tyres that can withstand the kind of sustained forces that would annihilate an F1 Pirelli, then maybe, just maybe it's possible even now. Maybe Koenigsegg can do it by modifying their 5.0 V8TT with the FreeValve system they're working on to get it up to 1500bhp. Maybe the supposed SuperVeyron will do it with a pointier nose and even more of VW's colossal engineering might on board. I think that before the end of the decade, we could well have a 300mph road car if these and other people stick at it and keep pushing.

Yes, the resulting car would be hideously expensive and, in real terms, irrelevant. But come on. Think how amazing it would be, even to see it go that fast, let alone be inside it. It is 26 years since the Ferrari F40 broke 200mph. I hope it's fewer than 30 years before the next great speed barrier is broken by something with number plates.

2 comments:

  1. Could a car like that carry enough fuel for the 90-mile straight? :-)

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    1. Well, hopefully they wouldn't need the whole thing to get the job done!

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