BOTB Asks: Will we ever see a 300mph road car? {{favouriteCount}} Quantity of Likes

28 Jun 2017

300mph seems a silly number, doesn’t it? The idea that someone could pass their driving test and (funds permitting, obviously) step into a car and drive it at 134 metres per second is pure fantasy and ridiculous, right?

Well maybe not. In 1987 the Ferrari F40 nudged past 200mph, which seemed incredible at the time, while it was almost 50yrs earlier that we crept past 100mph. So given how fast technology is progressing, do we need to wait until 2037 for a 300mph car? Given that the Koenigsegg One:1 is rated as having an (unverified) top speed of 273mph we’re definitely closer than further away. But what is it that’s stopping us from getting there?

Physics, mainly, though to simplify it even more – the biggest problem is air, or aerodynamic drag. As you’re driving your car, the engine is basically pushing the car through the air around us, and the faster you go, the harder it is to push through that air. Think of it as starting out as swimming in water, then soup, then thick oil, then custard, then… well you get the idea. The force required to push an object through the atmosphere increases at the cube of velocity.

To translate that into normal language: a car that needs 200hp to overcome drag at 150mph would need 1,600hp to reach 300mph. Now you see where the problems lie. The other problem are the tyres; the loads, heat build-up and stresses on a tyre at 300mph are enormous and tyre companies are working tirelessly to create tyre compounds and designs that can work at such high speeds. But we’re going to assume that this will happen, they’ll just be absurdly expensive (a Bugatti Chiron’s 270mph rated tyres cost an eye-watering £5000 each).

Bugatti Chiron

So it would appear that the answer is more power and better aerodynamic efficiency, but this in itself causes issues as the more power you have, the more cooling you require, which in turn means you need bigger intakes, which increases your aerodynamic drag, which means you need more power and on and on…

Who will it be then? Bugatti have stated that they aren’t going to chase 300mph with the new Chiron – it’s limited to 265mph thanks to the tyre issue, while Koenigsegg have also stated the same – so we must turn to the smaller companies to do it. Hennessey make the Venom GT which has been clocked at over 270mph, but they’ve just announced their Venom F5 (below), which will have a 290mph top speed thanks to the 1400bhp motor.

Hennessey Venom F5

Of course there are the vapourware companies who make endless promises and digital renders but never produce anything. The latest in the 300mph arena is the Dagger GT (see bottom of article), the product of a racing car manufacturer in the US. Their car will have around 2500bhp (allegedly) which will allow their car to have a 315mph top speed. Erm, yeah we’ll believe it when we see it.

The key is actually making a 300mph car driveable on the road though – there are hundreds of triple-ton cars that run every year on the Nevada Salt Flats, but they are only good for a straight line. The beauty of the Chiron is that it can do 265mph one minute, then pull off and pop to the shops without overheating the next. This is where the depth and breadth of engineering required to get a proper road legal car to be usable and reach 300mph is realised.

We’d put our money on it being a small independent company that will reach it first, but the car will be useless at anything else. This will then spur the big boys on and then Bugatti or Koenigsegg will make a drivable 300mph car. Or the tyres will be developed sooner and we’ll see a Chiron Supersport with 1800hp hit the magic number. We can’t wait to find out.

Dagger GT