New downsized twin-turbo V8, producing in excess of 650bhp and 550lb ft, destined for 458 successorFerrari will launch a twin-turbocharged V8-powered replacement for the 458 Italia at the Geneva motor show next spring, marking the start of a new era under chairman Sergio Marchionne.
The new car is a reskin of the aluminium platform that underpins today’s 458. The car’s project name is 142M — M for modified, 142 being the project number of the 458.
The new two-seater is expected to break fresh technical ground for a ‘mainstream’ mid-engined Ferrari by featuring a twin-turbo V8. It is based on the California’s 3.8-litre unit and test mules have been running it for some time.
Modified with dry-sump lubrication compared with the wet sump in the California, the V8 will have a capacity below 4.0 litres to comply with an influential Chinese tax threshold. Currently, the 4.5-litre V8 in the 458 suffers high taxes in China, hampering sales.
The California’s V8 has a capacity of 3855cc, based around an 86.5mm bore diameter, shared with the 3798cc Maserati version. To raise capacity, the California’s has a slightly longer stroke.
For the new 458, Ferrari must select the V8’s stroke carefully to ensure ‘over-square’ dimensions for a short stroke to promote peak power delivery at high engine revs.
A 4.0-litre capacity, for example, would be delivered with a relatively long stroke of 85mm, very close to the 86mm bore. In comparison, the outgoing 458 engine has a 94mm bore and a much shorter stroke of 81mm.
Ferrari may even need to select a stroke of 75mm, equivalent to just 3.5 litres, to maintain similar engine geometry to the rev-happy V8 in today’s 458. However, whether that is sufficient to generate the required power is a point for discussion.
The target car for the new 458 will be the 641bhp McLaren 650S and there are suggestions the Ferrari might be rated at 666bhp. To develop 666bhp from under 4.0 litres, the new V8 will have to produce 168bhp per litre, and from 3.5 litres 192bhp per litre.
To achieve that, the engine will feature a relatively high 12:1 compression ratio, aided by Ferrari’s ‘ion’ knock detection system, which adjusts combustion conditions individually in each of the eight cylinders.
The engine’s capacity is also likely to form the car’s name, a tradition started by the 206 Dino in 1968 — a 2.0-litre V6. A 3.5-litre V8 opens up the possibility of 358, a 3.8-litre 388 and a 4.0-litre 408. By adding a T, Ferrari might denote turbocharging. However, experience suggests that Ferrari is just as likely to opt for a new naming direction.
Other aspects of the new 458’s engine design are likely to diverge from the California’s, too. “Do not expect the same induction system as the California,” one source told Autocar.
One possibility is an electrically powered turbo. Ferrari is known to be experimenting with this technology, although it requires a 42V electrical system, which is probably too expensive to reverse engineer into an existing architecture. More likely is a conventional twin-turbo set-up, with two low-inertia turbo units that allow instant throttle response and high peak power at the expense of torque.
One of the challenges facing Ferrari’s powertrain engineers is how to reliably match a 650bhp-plus, 550lb ft-plus torque output to the seven-speed Getrag ‘7DL750’ dual-clutch automatic gearbox employed on all models from the California up to LaFerrari. Peak torque from the California’s 553lb ft V8 was set at the ’box’s limit and is only delivered in seventh gear. In the six lower gears, it’s limited to 400lb ft.
Autocar understands that developments are in the pipeline for the Getrag ’box, but whether that means beefier internals or an extra gear, for example, is unclear.
Styling is said to be the work of the in-house Centro Stile Ferrari design chief Flavio Manzoni and it is likely to be evolutionary. Developments in aerodynamics are likely to lead changes, with the front-end graphic centred around aggressive twin intakes.
Read the Ferrari California T review
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