Six Sells: Stellantis Introduces Twin-Turbo Inline-Six for Ram, Jeep

The auto industry might be moving headlong into all-electrics but that doesn’t mean internal combustion is dead, not by a long shot. Witness the introduction of a brand-new engine from Stellantis, a turbocharged inline-six that will be capable of generating more than 500 horsepower.

Development of this ‘Hurricane’ I-6 was kept on the down-low, at least as much as can be expected during these modern times when everyone has a camera in their pocket. Two variants will be available when the engine goes into production and pops up in showrooms later this year.

Stellantis says the Hurricane will offer its twin-turbo muscle using a broad and flat torque band, one which will see this mill maintain at least 90 percent of peak torque from 2,350 rpm all the way to its red line. Specific horsepower numbers will vary based on vehicle application, but the Standard Output will make somewhere in the neighborhood of 400 horses and 450 lb-ft while the extra-boosted High Output should knock on the door of 500 ponies and 475 units of twist.

Each turbocharger in the Hurricane twin-turbo I-6 feeds three cylinders, passing compressed air through an engine-mounted water-to-air charge air cooler to reduce its temperature before entering the intake manifold. The turbos on the Hurricane SO deliver a peak boost of 22 psi, while snails fitted to the Hurricane HO deliver 26 psi of peak boost.

And to answer the inevitable questions from gearheads in our audience: There is a difference in compression between the two brothers. Standard Output engines use cast aluminum pistons with a cast iron top ring land insert, running a 10.4:1 compression ratio. High Output variants deploy forged aluminum pistons with an anodized top ring land and a diamond-like coating on the pins, resulting in a 9.5:1 compression ratio on 91 octane premium fuel.

Bore, stroke, and cylinder spacing are shared with the globally-produced 2.0-liter turbocharged four-banger currently found in rigs like the Cherokee and Wrangler 4xe. The latter gives us a clue that this engine is likely to see a plug-in hybrid variant of some sort in the future. The non-electrified engine announced today will be assembled in Mexico.

Where will we see this engine? Stellantis ain’t saying other than to state the Hurricane twin-turbo I-6 is the primary internal combustion power plant of the future in North America for vehicles using the STLA Large and STLA Frame platforms. The smart money has it showing up in the Wagoneer, usurping the V8 and fitting the silky-smooth mandate of that luxury SUV very well. Logic dictates we’ll see it in Ram pickup trucks as well, with the venerable 5.7L Hemi (which has made 395 horsepower ever since Adam was an oakum picker) likely to soldier alongside in the short term, at least in the Ram 1500 Classic. This strategy is not without precedent since Ford has long offered turbo six-cylinder engines alongside the 5.0L V8 in its F-150. The octopot now comprises but a small portion of F-150 sales.

[Image: Stellantis]