Stellantis has debuted its 2.0-liter Hurricane 4 Turbo four-cylinder, with an output – 324 horsepower at 6,000 rpm and peak torque of 332 lb.-ft. from 3,000-4,500 rpm – that gives it the muscle to confidently propel a variety of vehicle sizes, ranging from compact to full size. The engine design includes flexibility for conventional, hybrid and plug-in hybrid powertrains.
“The Hurricane 4 Turbo name is appropriate because this engine packs a punch, as the variable geometry turbocharger, the high-performance combustion and the twin fuel system deliver 162hp/l of displacement,” said Micky Bly, Stellantis senior vice president and head of global propulsion systems. “The clean sheet design gives our customers a powerful, refined, smooth-running engine that uses 10% less fuel to deliver 20% more power than our current 2.0-liter DOHC I-4.”
The first application for the Hurricane 4 Turbo will be the 2026 Jeep Grand Cherokee.
Combustion technology
Central to the Hurricane 4 Turbo’s fuel-efficient power is the turbulent jet ignition (TJI) combustion technology, typically used in top-tier racing engines.
The passive TJI system in the Hurricane 4 Turbo uses a spark plug to ignite a small amount of fuel in a cup-like pre-chamber atop each cylinder. The burning fuel expands and jets into the combustion chamber, triggering a faster and more complete burn of the air-fuel charge, which enables better performance and fuel efficiency.
Stellantis engineers have combined the TJI combustion and turbocharging with a Miller Cycle operating strategy that closes the intake valves early to optimize engine efficiency and reduce emissions. This enables the Hurricane 4 Turbo to use a power-generating 12:1 compression ratio without risk of engine-damaging knock (early ignition) while using regular (87 octane) gasoline.
Each cylinder of the Hurricane 4 Turbo has two spark plugs, one for the TJI chamber and one for the combustion chamber. Ion sensing is used for misfire detection.
Efficient power and performance
The Hurricane 4 Turbo engine combines port fuel injection and high-pressure direct injection (350bar/5,076psi), with the engine controller deploying either system — or both— based on operating conditions. During cold starts, both systems activate to speed catalytic converter light-off. At idle and low loads, port injection minimizes NVH and particulate emissions. Under typical power demands, both systems operate with a variable ratio, while at peak power and maximum torque, direct injection supplies most of the fuel.
The Hurricane 4 Turbo features a variable geometry turbocharger with active vanes, producing up to 35psi (2.4 bar) of boost. It delivers strong low-rpm power and torque, providing 90% of peak torque between 2,600 and 5,600rpm. Pressurized air from the turbo passes through a liquid-to-air charge cooler, lowering intake temperatures for a denser, more powerful combustion charge. The design enables Stellantis engineers to achieve high-power density without compromising low end torque and transient performance, while keeping the overall package compact, compared with a conventional twin-scroll turbocharger.
The engine also uses an electric-powered water pump and a variable displacement oil pump to reduce parasitic losses.
Solid foundation
A die-cast deep skirt aluminum block, produced by Stellantis, provides a solid foundation for the Hurricane 4 Turbo.
The engine’s structural stiffness is enhanced to help minimize noise, vibration and harshness – thicker cylinder bore walls (24% thicker compared with the current 2.0-liter DOHC I-4) and larger main and connecting rod bearings on the crankshaft. A structural windage tray and balance shaft assembly is mounted low in the engine. A viscous crankshaft damper helps reduce vibrations.
The aluminum cylinder head contains four valves per cylinder and overhead camshafts. The TJI chamber is press-fit into the center of each combustion chamber for simplified assembly. Variable intake timing is adjusted quickly by an electric camshaft phaser, which delivers smoother startups. Exhaust valves are sodium-filled for heat management.
The engine also features an ultra-thin, low-friction plasma transfer wire arc (PTWA) coating in the cylinder bores. Compared with conventional iron cylinder liners, the PTWA coating has 10 times the wear resistance.
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