Hennessey reveals 1817bhp F5 Venom

il y a 3 années, 11 mois - 17 Décembre 2020, autocar
Hennessey reveals 1817bhp F5 Venom
Carbonfibre-bodied, V8-powered American hypercar targets road car speed record

Long-established US tuning company Hennessey has launched its first fully bespoke hypercar, with which it aims to break the road car speed record, thanks to a maximum in excess of 311mph.

First previewed with a styling model in 2018, the carbonfibre-bodied F5 Venom is differentiated from 2011's ultra-low-volume Venom GT by utilising an in-house platform instead of a heavily modified Lotus chassis. Autocar has seen the first fully constructed car in the UK ahead of its dispatch to the US.

Hennessey claims the combination of an 1817bhp twin-turbocharged V8 petrol engine and a 1360kg dry weight help make it one of the fastest road-legal cars in the world – possibly even the fastest. The company also predicts a 2.6sec 0-62mph time, a 4.7sec 0-124mph time and an 8.4sec 0-186mph time.

Named after the highest rating on the Fujita hurricane strength scale, the F5 Venom uses a carbonfibre monocoque, built by KS Composites in the UK, that weighs just 86kg naked. A rear tubular aluminium subframe contains a 6.6-litre overhead-valve Fury V8 built by Hennessey in Texas with a cast-iron block, aluminium heads, forged connecting rods and pistons and a crank and camshaft made from billet-steel. This is boosted by a pair of ball-bearing turbochargers with 3D-printed compressor housings that can deliver up to 1.58bar of boost.

In addition to the headline power figure, which is delivered at 8000rpm, Hennessey claims a torque peak of 1193lb ft, with at least 1000lb ft available from 2000rpm through to 8000rpm.

CEO John Hennessey says the use of a pushrod engine was due to the more compact dimensions and lower centre of gravity, as well as his company's expertise in extracting power from them; Hennessey Performance Engineering already offers a twin-turbo 1200bhp upgrade for the C8 Chevrolet Corvette.

Power is delivered to the F5 Venom's rear wheels by a CIMA seven-speed single-clutch automated transmission and a limited-slip differential.

The obvious differences between the production car and the concept are mostly aerodynamic, with the loss of the raised wing and the use of a substantially larger diffuser. Unusually for this class, there are no active aero elements.

Production director David Davis says the aim has been to create enough downforce for high-speed stability without creating excessive drag. The concept's targeted 0.33Cd drag coefficient is now a still-respectable 0.39Cd.

Beyond that, the car looks very similar to the concept, with butterfly doors and decent passenger space for a hypercar, with the well-finished combination of leather facings and carbonfibre trim. There are some other impressive details, including the fact that the entire rear section of the car is made from one piece of carbonfibre with CNC-machined vent holes.

Despite its enormous performance, the F5 Venom has been designed to stay drivable at lesser speeds and to cope with roads and tracks as well as it does v-max runs.

The double-wishbone suspension uses passive dampers, but these can be adjusted for bump and rebound, and the car also offers five selectable driving modes, including Drag for acceleration and F5 for ultimate speed.

While the first F5 Venom has been built in the UK, the others will be assembled in Texas – and offered in Europe under IVA homologation. Production will be limited to 24 cars, with a pre-tax price of $2.1 million (£1.58m). John Hennessey says he has taken deposits for half of those already.

Confidence in reecord potential

John Hennessey is adamant that the F5 Venom will be "considerably faster" than the old Venom GT, which recorded a 270.49mph two-way average at the Kennedy Space Center in 2014. His plan is to prove its performance with what he hopes will be a recognised production car speed record. The issue, he admits, is the limited space available on the Nasa runway.

He said: "From end to end, from the grass to the swamp, it's 3.4 miles. The GT was still accelerating when it had to brake. I reckon with the F5, in ideal conditions, we will be approaching the 300mph range there, but I don't know if we have enough room to beat Bugatti's number [304.77mph] down there. I think if we're going to try for absolute v-max, we're going to have to do it on a road somewhere."