Thanks to Danno, Patfromigh, and Steven St. Laurent. Updated May 17, 2016 (photos).
The new “Hurricane” four-cylinder is named after another fighter plane — but the same name was used for a long-gone Jeep engine. Sources have told Allpar that the goal is for one Hurricane to reach 250 horsepower or so, and for another to meet or beat 300.
Timing is uncertain at this time, with most believing the Chrysler version of the Hurricane will not appear until 2017-19. However, Alfa Romeo is using a 276 horsepower MultiAir biturbo version on the Giulia, for the US; it has a flat torque curve of 295 lb.-ft. of torque between 2,250 – 4,500 rpm; the “2-in-1” turbocharger uses two pipes that gather exhaust gas from pairs of cylinders in alternating sequence.
Chrysler tested two-stage turbocharging (illustration on right) in a Department of Energy project, with a small and large turbo to reduce lag without hurting power. Insiders say this is not likely to make it to the production engines, due to cost; instead, a single twin-scroll turbocharger seems to be planned. It is likely to be relatively small but have a very high rotation speed, compared with past Chrysler turbochargers.
The 2.0 turbo could replace the 2.4 liter engine in most cars, and substitute for a V6 for many people as well.
According to “AutoTechnician,” the offset crank reduces cylinder wall side loading and reduces the engine’s height (as may a recent patent for in-the-heads valve timing controls). The connecting rod is more vertical during the power stroke, reducing the force of the piston against the cylinder walls, reducing friction.
One source who has seen the Hurricane Four said it externally resembled the current World Gas Engine in some ways, and the Pentastar in others; it has a plastic valve cover for reduced weight. However, it jettisons the WGE block completely, and moves to the new GME series.
Powertrain chief Bob Lees’ 2014 presentation pointed out that Fiat Chrysler had eleven different small engines (mostly on the Fiat side since Chrysler only has two), and was planning to replace those with one engine family in two displacement-per-cylinder sizes (leaving open the possibility of two, three, and five cylinder setups).
No timeline was given.
Alfa Romeo has a 1.75 liter four, Fiat has the 1.4 series, TwinAir, and others, as well as the Brazilian e.TorQ, and Chrysler has their current 2.0 and 2.4. The Hurricane may be the first of a new generation.
An illustration from the financial presentation shows that the future global small engine family will include, though not necessarily on every engine, a twin-scroll turbocharger, a belt starter generator stop-start system, MultiAir, direct injection, a timing chain, and cooled EGR for efficiency. Internal features are a low-friction balance shaft, variable flow auxiliaries, low-friction timing chain, and lightweight crankshaft.
A recently granted patent (applied for back in 2011 by Chrysler’s Richard H. Sands and Alan G. Falkowski) can cut Chrysler’s costs and reduce the size of their engines, helping the company to either fit larger engines into their cars, or to lower their hoods for better aerodynamics and sportier shapes.
The patent applies to in-line and V-engines alike, which means it could be used for the upcoming Hurricane turbocharged four-cylinder; but the drawings and a specific size example are taken from a V6 engine, presumably the PUG (Pentastar Upgrade).
The new setup would integrate valve controls into the head, rather than having them sit on the outside with a separate cover; passages inside the head would provide access to the valves. This would save space and reduce cost. Thanks, Steven St. Laurent.
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