https://www.allpar.com/news/2018/12/the ... -six-43175
A brand new FCA in-line six-cylinder engine, turbocharged to meet or beat 5.7 Hemi power ratings, with a smoother torque curve, is on the way. The first vehicle to get it might be the Jeep Wagoneer or the next-gen Grand Cherokee, but it’s also bound for the Charger and Challenger, and may replace the Pentastar as base engine on the Ram pickups.
To keep space requirements low, FCA is going to have to pull out all the stops, so it’s not likely to be a GME four-cylinder with two more holes tacked on. The engine will have relatively small bores, closely spaced, to reduce its length; Lancia and Volkswagen have some old tricks that may come into play. Since ever millimeter counts, Chrysler’s traditional steel cylinder liners may be rejected in favor of aluminum hardening. Reportedly, the goal is to stay within three inches of the current 2.4 liter four-cylinder.
The expected displacement is just under 3 liters, coming under a displacement-tax threshold, with power boosted either by twin turbos or by a twin-scroll turbo. The code name might be Tornado, or perhaps that’s wishful thinking; in any case, the engine coded Hurricane is known as the “2.0 liter four cylinder,” so it seems likely the GME-T6, even if nicknamed “Tornado,” will just be called the “3.0 liter six cylinder” in official statements.
Forced induction would likely be through twin scroll turbochargers for the Chrysler versions, and perhaps dual turbochargers for Alfa Romeo and Maserati, if they share it. Any Italian versions would most likely have Ferrari-designed heads and different blocks.
Straight sixes are inherently smoother than V6s, and have a bit of snob appeal, given their use by BMW (mainly) and by Mercedes.