Probably the biggest problem with the Gordon Murray Automotive T50 is getting your head around it.
The uninspirational name doesn’t really help; Murray gives all of his projects ‘T’ numbers and the 50 denotes that this is the one that celebrates the fact he has now been doing this for more than five decades.
But even on the limited information released, it has a spec sheet that looks like a supercar forum wishlist more than reality. This is a three-seat supercar with a central driving position, a naturally aspirated V12 engine that revs to 12,100rpm, a manual gearbox and an active aerodynamic system that uses a 48 Volt fan.
But to coincide with the launch of the first official image of the car – a rear shot showing off that 400mm fan – and a more detailed explanation of how the clever aero works, CarAdvice was invited to interview Murray himself.
'Legend' is an overused term, but the 73-year old South-African-born designer absolutely qualifies, the T50 representing the synthesis of two of his most famous ideas. The first, most obviously, is the McLaren F1; arguably the first hypercar and one that is still regarded as a high water mark by those capable of writing the increasingly sizeable cheques necessary to land one.
The other, less obviously, being the Brabham BT46B – the controversial “fan car” that won the only Formula 1 race it was ever entered in, using an engine-driven fan to suck air from its skirted underside and improve downforce.
Yet it turns out the T50’s active aero is much more advanced than the system he used on the BT46B, with the 48 Volt fan being used to strategically clean up airflow rather than try to vent the entire underside. Unless you’ve got a degree in engineering or aeronautics, the next bit probably has to be taken on trust.
“Normally diffuser air won’t follow anything more than a gradient of about 7.5 degrees, it just separates,” Murray explains, “so your diffuser shape has to be gentle. Every designer on the planet would love to have a very aggressive diffuser like this one, but the air will just say 'no thanks' and you end up with a pool of stagnant air where the diffuser has stalled, and the flow will just do its usual thing.”
The powerful fan is linked to the top of the diffuser through a set of controllable ducts, and it extracts the disrupted “boundary layer” or dirty air that has been caused by the diffuser’s aggressive angle.
“Once that’s out of the way, the air has to follow the surface,” Murray says, “at lower speeds you can generate much more downforce because the fan does the work – it’s not literally sucking the car down, but it is creating a much more efficient diffuser.”
We haven’t been given peak numbers yet – although Murray promises they will be impressive – but the important thing is the ability to create different amounts of downforce almost instantly. The T50 will make peak downforce in its braking mode, sucking itself to the ground in the event of a dropped-anchor stop, the system trimming a claimed 10 metres from the car’s stopping distance at 240km/h. But it also means it doesn’t run too much downforce at cruising speeds, when it isn’t required – something that many wing-covered hypercars are often guilty of.
In addition to a regular mode and a high downforce mode, which increases this by about 30 percent, the car will also have a slipstream mode, shutting off the valves into the diffuser and diverting the efforts of the fan to suck from two inlets on the T50’s rear flanks. This reduces drag and also creates what GMA claims is a “virtual longtail” through air expelled behind the car. “Drag drops by 10 percent, which is massive,” says Murray.
GMA has just announced a technical partnership with the Racing Point Formula 1 team – the one owned by Lawrence Stoll, the Canadian billionaire recently linked to a bid for Aston Martin – which will give GMA access to both Racing Point’s wind tunnel and considerable aerodynamic expertise.
Amazingly, the total weight of all the parts of this active aero set-up – electric motor, fan, wiring, ducting and valves – comes to less than 10kg, much less than the mass of the heavy hydraulic actuators that would be required for a conventional active wing. They’re part of a lightweight ethos that runs through every part of the car, even the mass of individual bolts and fasteners being considered to ensure the T50 meets its 980kg target.
The use of the 48 Volt fan, and also a 48V compressor for the air con system, dictated the use of a starter-generator rather than a alternator and conventional starter motor. As well as saving 4.8kg, this also allows a modest amount of electrical power to be added to the engine, the ISG putting in 30hp in what Murray calls “push to pass” mode. Together with the ram effect of air entering the central intake at speed that pushes total output to around 700hp.
The Cosworth-built naturally aspirated V12 engine is likely to be compared to the Cosworth-built naturally aspirated V12 that will power the Aston Martin Valkyrie. But beyond layout and lack of turbochargers, both are very different, the T50’s 3.9-litre unit being much smaller and lighter.
“I didn’t give Cosworth a power target,” Murray says, “but I did say it had to be as light as possible. They’ve done a fantastic job – it’s 60kg lighter than the F1 engine.
Also keener to rev. Indeed, keener to rev than anything – Cosworth delivering on Murray’s target of a 12,100rpm redline. Response was also key; Murray says that the McLaren F1 was able to add 10,000rpm a second, owners loving its “waap-waap” sound when revved hard. Cosworth was asked to better that, but pretty much blew it out of the ocean: the T50’s jewel-like V12 will be able to add 28,000 revs a second. Murray says there will be two engine modes, one that runs out at around 9500rpm - “what we call Ferrari revs” – and the second that gives the lot.
“That’s the one for when you say to your mate “do you want to hear 12,000rpm going through the tunnel?” Murray says.
The six-speed manual gearbox is an indication of both Murray’s commitment to mechanical purity, but also an indication that T50 buyers will be expected to bring a level of driving talent to ownership. Murray says the majority of the 100 road-going T50s have already been sold, and the presence of a clutch pedal was only an issue to one potential buyer.
There will also be 25 track-only versions which will feature motorsport sequential transmissions.
“That’s going to have three times the downforce of the road car, and at the speeds you’re going to be doing around a track it doesn’t make sense to be worrying about gears,” Murray says. It will also have fixed wings.
Although around 40 percent of T50 buyers are under the age of 45, many of the older ones already possess McLaren F1s.
“I had an F1 for a while and when they start getting up to $10m or $15m – now even $25m – you’re not sure about taking them out in the wet and sliding them about to show your friends what fun it is,” Murray says, “here’s one for a fraction of the price they can go and thrash to death. Several buyers have told me that’s exactly what they are going to do with it.”
We’d be disappointed if they didn’t. The T50 is going to be formally unveiled next May, and we look forward to learning more about it then.