Overview: Arash AF10

The Arash Motor Company was formed in 2006 with the aim of building a supercar: a specific car, whose lines had already been sketched out a few months before. The Company has been working on that project, now called AF10, ever since.

Arash has its headquarters at Sawston near Cambridge. The Sawston facility is equipped with a styling studio, painting booth, carbon-fibre lamination room, carbon-fibre curing autoclave and car assembly stations. Here the styling sketches were digitised and converted into computer models for CFD (computational fluid dynamics).

Although the AF10 has now been prototyped and is visually close to its finished form, its is still very much a work-in-progress. Track testing is about to begin as we write (October, 2010) at Millbrook proving ground.

Bodyshell

As you will have gathered from the previous comments, carbon-fibre is used in the AF10’s construction. In fact, the entire structure is built in the Formula One idiom, with tiaxial-weave carbon-fibre panels sandwiched with aluminum honeycomb and Nomex; the latter provides good heat resistance. The AF10’s central ‘tub’ weighs 98kg: by way of comparison, the McLaren MP4-12C’s weighs under 80kg, though it is physically smaller. Unlike the McLaren, the front and rear structures of the Arash are fabricated from steel tubing rather than aluminium.

Triple galleries under the chassis allow packaging of the coolant pipes, air conditioning pipes and brake lines, while the underfloor itself is flat. The twin lightweight aluminium fuel tanks are integrated into the rear chassis pontoons.

The car’s rear window, and that between the driver and the engine compartment, are made from non-shatter, scratch-resistant plastic. The door-windows and windscreen are laminated glass.

A full steel roll cage is integrated into the structure, providing extra torsional stiffening as well as crash protection.

Inside, floor mounted pedals are used to provide a racing feel and better heel-and-toe control.

Running-gear

The AF10 uses wishbones front and rear for its wheel location. The arms are hand-made from aluminium, and nickel coated: this offers protection against corrosion and also provides a means of visually identifying cracks due to damage. A strut brace is integrated into the carbon-fibre tub to minimise flexing.

The brakes are ventilated carbon ceramic discs; eight-piston AP racing calipers with 380mm discs are used at the front, six-piston AP racing calipers and 362mm discs at the rear. Road wheels are two-piece aluminum items, 19"x9.5" at the front and 20"x12.5" at the back. Standard tyres are Michelin Pilots: 265/35Z for the front, 335/30Z at the rear.

Perhaps reflecting the Arash Motor Company’s modest size, there are no clever electronic controls changing damping rates according to driving conditions. The driver must drive the car as it comes. Whether this is seen as a woeful omission or a glorious triumph of old-school motoring values will depend upon the price at which Arash sells the car. If we were to choose between a carbon-fibre body or electronically-controlled suspension, brakes and torque-vectoring, we would pick the carbon shell every time — assuming it’s set up well.

Engine

Update: We knew the AF10 was a work-in-progress, but we weren’t expecting Arash to pull an all-new engine out of the hat. Nevertheless, that is what has happened: on 5 November, the Company will announce its new power-plant for the AF10, an 850PS V10 designed in-house. For the moment, that’s all we know. The two paragraphs below relating to the General Motors LS7 engine are now of historical interest only.

Additionally, the stock Graziano transmission specified in conjunction with the G.M. V8 has a torque limit of 750Nm, and is not likely to be adequate for the new engine without a degree of re-specification.

The power-unit Arash has chosen for the AF10 is distinctly old-school. It is G.M.’s LS7, a seven-litre V8 hand-built at General Motors’ Performance Build Centre in Wixom, Michigan, for — in stock form — the Chevrolet Corvette. The unit is also available as a ‘crate’ engine, and is used for racing in the U.S.

The 7011cc LS7 is based on G.M.’s Generation IV architecture. It features a traditional 90° V angle, all-alloy construction and dry-sump lubrication. Pressed-in cylinder liners are used. The crankshaft and main bearing caps are forged steel, the connecting rods are forged titanium, and the flat-top pistons are hypereutectic aluminium. There are two valves per cylinder; the titanium intake valves are 55.9mm in diameter, while the sodium-filled exhaust valves are 40.9mm items. The ports and combustion chamber are CNC-machined for good and consistent gas-flow, and the unit runs with a remarkably high 11.0:1 compression ratio. Peak outputs in stock form are 512PS at 6300rpm and 640Nm at 4800rpm, with a 7000rpm red line. The version used by Arash, which has shorter exhausts, different intakes and a reprogrammed engine management map, is rated at 557PS at 6000rpm and 644Nm at 4800rpm, with the same 7000rpm maximum. By way of a comparison, the McLaren MP4-12C’s 3.8-litre turbocharged power-plant delivers around 600PS at 7000rpm and 600Nm at 3000rpm (these figures are provisional).

The V8 drives through a Graziano GT-ME1 six-speed manual transmission. Mounted in the steel rear subframe, it features pressure lubrication and an oil cooler. The final drive unit has limited slip. Arash is presently using a conventional mechanical linkage for the box, and although we do know that this unit can be automated, we can’t see the AF10 being offered with this option. Graziano also supplies the seven-speed dual-clutch transmission for the McLaren 12C, and Arash is much more likely to see a derivative of this unit as an option for the future.

Arash
AF10
Cylinders 8V
Valves 2
Bore/stroke 104.8/101.6
Swept volume 7011cc
Compression
ratio
11.0:1
PS/rpm 557/6000
Nm/rpm 644/4800
Maximum speed 205 (est)
0-100km/h TBA
Urban MPG
(l/100km)
TBA
Combined MPG
(l/100km)
TBA
CO2 g/km TBA
Emissions TBA
Transmission
— 1
— 2
— 3
— 4
— 5
— 6
— Final drive
M6
3.15
2.18
1.57
1.19
0.94
0.76
4.10
Driven wheels Rear
Fuel tank TBA
Kerb mass TBA
Length 4663
Width 2050
Height 1145
Wheelbase TBA
Track: front
— rear
TBA
Cd TBA
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