John Hennessey vs Wolfgang Dürheimer: TG chats to the 300mph masterminds
Hitting 300mph in a highway automobile. What are the challenges? Is it even achievable? The present quickest pace in a highway automobile is 270.49mph. It’s held by a Hennessey Venom GT, solely 2.63mph above the Bugatti Veyron Super Sport, and achieved in just one course. Clearly, at these speeds, including one other 1mph is troublesome, so how doubtless is it that their next-generation vehicles – the Chiron and Hennessey’s F5 undertaking – will have the ability to add one other 30mph to that?
Words: Ollie Marriage
Indeed, is 300mph even on their radar, or is it a step too far? At 300mph (482.8kph) 100 metres would take zero.746secs. If it occurred in a stadium, you possibly can barely flip your head quick sufficient to maintain up. Over to Wolfgang Dürheimer (outgoing Bugatti CEO) and John Hennessey (founding father of Hennessey) to inform us extra…
So, Wolfgang, what would you say are the primary challenges of going very quick in highway vehicles?
Well, if you find yourself out to interrupt new floor in an space the place no one was up to now, you can not 100 per cent predict the issues you’ll face. But it begins with the tyres, as a result of at that pace you’ve gotten a stress load on the tyres, particularly on the floor, that’s immense. Once once more, we’re working with Michelin – I feel we’re their most difficult tyre-development associate – however in the entire of Europe, we didn’t discover a take a look at bench to manage by way of sturdiness and high-speed functionality.
We truly discovered a bench within the US that’s used for plane tyres, and it’s been used to extremes to ensure the tyres are secure sufficient.
Click right here to observe Chris Harris drive the Bugatti Chiron
After tyres comes aerodynamics?
At excessive speeds, aerodynamics and energy are very carefully associated. To go quick, you want the ability of the engine to interrupt the barrier and to compensate for the aero drag you construct up – it’s like transferring a bookshelf by the air. Aerodynamics on the Chiron took all of the computational energy we had within the Volkswagen Group, as a result of whenever you strategy 400kph, life, in driving dynamic phrases, will get very demanding, and it takes numerous effort to develop the aerodynamic stability so the automobile is predictable and secure in all circumstances.
Can you mannequin the whole lot on computer systems?
Not the whole lot. When you’re at these limits, pushing the boundaries, you don’t know what you may discover, so it’s essential not simply to have a look at computer systems, however to drive and take a look at the automobile. Let me offer you one instance. We have been in South Africa to do high-speed checks with the automobile in its remaining design, and we realised once we went at very excessive speeds for an extended time period the single-beam lightbar and carbon-fibre components on the rear began melting as a result of extraordinary exhaust warmth – roughly 1,000 levels Celcius when it comes out of the pipes.
So we needed to develop an air duct on the surface of the exhaust that ejects the new fuel out about 80cm additional behind the automobile, after which it was superb.
The strain inside the engine have to be enormous?
It was fairly a problem so as to add 50 per cent on prime of the Veyron’s 1,000 horsepower from the identical displacement. To go 400, don’t begin under a thousand horsepower and to go, let’s say, 450, don’t begin under 1,500bhp. You is not going to make it. There are 1000’s of items on this engine, and so they all must maintain the stress load – we have now to carry one cubic metre of air per second by the combustion chamber and out once more. But we knew we wanted this energy to strategy the 450kph restrict.
When we went at very excessive speeds for an extended time period the single-beam lightbar and carbon-fibre components on the rear began melting as a result of extraordinary exhaust warmth
450kph is 280mph. Are you meaning to go for an even bigger pace than 261mph in the usual automobile?
While the automobile will stay restricted at 420kph [261mph] for public roads, we’ll attempt to do one other world pace file for street-legal vehicles almost certainly in 2018. This will occur underneath managed circumstances on our take a look at monitor.
And 450 is an achievable goal?
It may very well be attainable, however we don’t know but, we’re nonetheless testing.
Are you trying past that as nicely? Or is that the road within the sand?
Nobody attracts a line within the sand, I feel the race goes on, and when somebody crashes the 450 barrier, somebody will strive 451 a 12 months later. But on this recreation, you can not predict what’s going to occur. You must watch out, management the circumstances, have the fitting air, wind, highway circumstances. But that is what we love to do, and it’s the massive issue of differentiation in Bugatti, that we do that and inform our clients what the vehicles are succesful of.
Top pace nonetheless sells, then?
Power, pace and lap occasions are what sells.
But the Chiron isn’t a lap-time automobile…
No, however the automobile has its personal guidelines, and on a monitor like Le Mans the place we have now an ultra-long straight, that is the El Dorado for a Bugatti. Fast and lengthy turns are our area.
How a lot does being first matter? How essential is it to have a rival?
Of course it’s good to have competitors. To solely beat your self will not be what we’re on the lookout for. But is it essential for us to be primary? It’s in the end essential for us, as a result of we’re representing our clients, and our clients are primary wherever they present up. I all the time say in case you are available second you’re the first loser.
Will you do the high-speed runs at Ehra?
Ehra is a playground for us – it’s like heaven. We have the last word straight and predictable circumstances – we all know what the wind’s doing, and the monitor is correct in entrance of our door.
Is 300mph a risk for the Chiron?
No, I don’t suppose that’s a risk for the Chiron in its present form and sample.
But it have to be a barrier some clients have talked about to you?
Yes, however fortunately we live in a world of kilometres not miles, and at this time we’re speaking about reaching 450.
So nobody’s speaking 500, then?
Some clients requested me whether or not we’re approaching it, however I’ve no reply for this at current…
And now, over to John Hennessey, creator of the 270mph Venom GT, and its substitute, the 1,600bhp Venom F5…
So, John, what would you say are the primary challenges of going very quick in highway vehicles?
First, there’s the consideration of tyres, however I’m not too anxious about that as a result of I’ve received a automobile that weighs lower than 1,400kg, so I’m not working the tyres as arduous. So, for me, aero is most important. When we ran 270mph within the Venom GT, the drag issue was zero.44Cd – like a small pickup truck.
If we needed to get the Venom to go 300mph with the drag it has, we’d have wanted 2,500bhp. The aim for the brand new automobile was to go underneath zero.four, however it’s truly come out manner higher than that.
The smallest particulars make an enormous distinction on whether or not you’re going to have the ability to do 250mph or 270. On the Venom we performed with many designs for the rear diffuser, and so they had enormous results, altering the aero stability, placing an excessive amount of warmth within the tyres and so on.
Was that utilizing laptop simulations?
Yeah. The computer systems are fairly darn good. Nine years in the past, once we first did Computational Fluid Dynamics on the Venom GT, they mentioned that with 1,200bhp the automobile would go 272mph, and once we needed to shut down at NASA at 270, the automobile was nonetheless accelerating, there have been a couple of extra mph in it – the drag and thrust would have equalised at about 273 to 275. Now they’re much more scarily correct. But for each one factor we all know, we’ve tried 10.
How in regards to the engine for the brand new automobile?
It’s to be decided. It’ll be turbocharged – twin turbos are straightforward to do and package deal. My youngest son mentioned why not put 4 turbos on it? Well, we are able to, however it’s a little bit extra difficult, and I like simplicity.
How a lot energy will it have?
The calculations say about 1,530–1,550bhp is required to do 300mph. I’d prefer to cowl that with a little bit additional. And with the [Koenigsegg] Regera and [Bugatti] Chiron each about 1,500bhp, I’d prefer to have a little bit extra.
Sounds such as you firmly imagine 300mph is achievable?
I do. And I’m positive the Bugatti guys do too. They have a unique set of challenges, however I feel my automobile’s doubtlessly able to 500kph [311mph].
500 is an insane quantity, I’m solely aiming for 300mph in the meanwhile. I don’t know the way a lot energy we’d want, however say it’s 2,000bhp to go 500kph, nicely that’s type of possible.
Where are you able to go to do it?
Maybe we have now to go to Bonneville, however that has its personal set of challenges since you’re operating on salt at four,000ft of elevation, with bizarre climate, and you may spin the tyres at 200mph. The NASA runway is three.2 miles and that’s simply not lengthy sufficient. When we ran 270, it took 2.four miles of acceleration and zero.eight to brake. Closed roads are difficult as a result of the smallest bumps at these speeds would doubtlessly be catastrophic. There’s typically a excessive crown, it’s slender and there are critters – and a critter strike at excessive pace is dangerous information.
My youngest son mentioned why not put 4 turbos on it? Well, we are able to, however it’s a little bit extra difficult, and I like simplicity.
How essential is it to you to have competitors?
If we exit and do a run, that’s cool, however it’s not practically as cool as whenever you’ve received the highway runner and coyote collectively. Then we’re speaking in regards to the 300mph membership, and that’s cool. It’ll be a enjoyable subsequent three to 5 years. I’ve heard Bugatti goes to exit and do a high-speed run within the Chiron subsequent summer season, which I’m assuming will beat our 270mph. After that we’re going to play our recreation and hopefully we are able to have some leapfrog alongside the manner.
Do we intend to do 300mph subsequent 12 months? No. We’ll do it once we’re able to do it, and if Bugatti will get there first, then congrats to them. It’s troublesome to do. If they get to 300mph earlier than us, we’ll finish the sport at 500kph.
Will that be the top, then?
Are you asking if there’ll ever be a 400mph membership? No manner. At least not for an additional quarter of a century. I used to be trying on the historical past of 200mph and also you had the Porsche 959 and Ferrari F40 after which Ruf. Now the whole lot is able to 200mph. So 300mph is the Mount Everest.
I’m positive the Merc Project One will go 6:30 across the ’Ring and folks will discuss s**t about it, saying they did it with cheater tyres, however that’s why I like vmax – you’ll be able to’t argue in opposition to a vmax run. It’s absolutely the quickest, and I don’t like qualifiers: the quickest at such-and-such monitor, or the fastest- accelerating to such-and-such pace.
I don’t need to be the quickest on the Nürburgring; I simply need to be absolutely the quickest. That’s what issues to me and my shoppers. So there’s the Chiron and I count on McLaren’s BP23 will go quick too, however I don’t need to run with these guys, I need to crush them. To be the quickest, interval.
And what of Koenigsegg? Top Gear requested firm boss Christian von Koenigsegg for his tackle the lure of 300mph…
Christian, after I drove the Regera final 12 months, you mentioned to me that 250mph is quick sufficient?
250mph is quick sufficient for most individuals. It’s the way you arrive there, how shortly, how safely, the emotional worth, that’s what issues. Having mentioned that, the Agera RS, with the one-megawatt improve will attain 270mph or one thing like that.
Does that matter to your clients?
To some, sure. We’re not bothered, however the clients are and we’ll help them. We’re not chasing it – it turns into extra irrelevant, as a result of these are highway vehicles, not dragsters.