Stellantis debuts new 3.0TT I6 Hurricane engine

STELLANTIS has unveiled details of its hotly anticipated Hurricane 3.0-litre inline six-cylinder engine. The twin-turbo charged mill is said to emit lower emissions and uses less fuel than larger displacement V8 engines, while delivering as much as 15 per cent more power and torque.

Stellantis says it will offer the engine in two states of tune – one designed for efficiency and the other for performance – and that the architecture is futureproofed to accommodate the hybridisation of the driveline in line with the group’s Dare Forward 2030 strategic plan.

In Standard Output (SO) form, the Hurricane unit provides “more than 400hp (298kW) and 450lb-ft (612Nm)” at 22psi (1.5bar) boost while the High Output version promises “more than 500hp (373kW) and 475lb-ft (644Nm)” at 26psi (1.8 bar) boost. Compressions ratios for the duo are listed at 10.4:1 and 9.5:1 respectively.

Stellantis says the motor’s output characteristics and ratings will vary based on which models it powers and that the first I6 powered variants will reach US dealership showrooms this year.

The Hurricane unit can be tuned to offer at least 90 per cent of its peak torque figure from 2350rpm through to redline, courtesy of a pair of low-inertia, high-flow turbochargers, each of which feeds three cylinders.

Turbocharger cooling comes via an engine-mounted water-to-air charge cooler, while innovative dual water-cooled exhaust manifolds are integrated within the cylinder head.

The dual overhead camshafts feature wide-range fully independent variable valve timing to maximise efficiency at lower engine speeds, while the fuel injection system is rated to 5075psi (350 bar). The engine also benefits from the application of a low-friction Plasma Transfer Wire Arc (PTWA) to the cylinder bores; this is said to offer ten times the durability of cast-iron sleeves.

The all-aluminium unit incorporates an alloy oil pan and features cross-bolted steel main bearing caps to contain the strong rotating forces generated by the Hurricane’s forged-steel crankshaft and -connecting rods.

An idle-stop system with a “robust starter motor for quicker restarts” is also featured, Stellantis says, while both the lubrication and cooling systems operate on-demand to reduce frictional and mechanical losses.

Built at the group’s Saltillo Engine Plant in Mexico, the 3.0-litre Hurricane twin-turbo I6 shares design features, including bore and stroke and cylinder spacing, with the globally produced turbocharged 2.0-litre I4 found in selected Wrangler, Wrangler 4xe, Cherokee and Grand Cherokee 4xe variants.

It will make its way into future models, including those built on the group’s STLA Large and STLA Frame platforms, within the next 12-36 months.

“As Stellantis aims to become the US leader in electrification, with a 50 per cent battery-electric vehicle mix by 2030, internal combustion engines will play a key role in our portfolio for years to come, and we owe it to our customers and the environment to provide the cleanest, most efficient propulsion possible,” said Stellantis head of propulsion systems Micky Bly.

“The Hurricane twin-turbo is a no-compromise engine that delivers better fuel economy and an important reduction in greenhouse gases without asking our customers to give up performance.”