Pentastar (née Phoenix) Engines: Chrysler V6 Engines for 2011 and Beyond

Motores Pentastar en español

At least one observer said that the Phoenix / Pentastar engines were at least a generation ahead of anything currently available. Power ratings for the Jeep Grand Cherokee will be 280 horsepower (209 kW) and 260 lb.-ft. of torque (353 N•m) @ 4,800 rpm; the engine uses a chain drive instead of a timing belt for greater longevity and accuracy. The engine was first shown to the public on April 8, 2009.

A twin turbo and single-turbocharger version are planned, for introduction by 2014; both would be based on the smallest size (3.0 liters) and might be slated for limited-production models (e.g. a new Viper based on a Maserati or an SRT mid-sized car). The twin-turbo version appears to projected for a whopping 420 horsepower while the single-turbo appears to be set for 370 hp.

A 3.3 liter version with MultiAir would top out around 280 hp, along with the current 3.6 liter version; a base 3.3 without MultiAir or direct injection seems to be slated for around 260 hp.

Here are some of the major innovations, as far as we can tell:

• All accessories bolted directly onto the block to avoid vibration and noise
• Exhaust manifold apparently integrated into the head itself
• Oil to antifreeze oil cooler in the "V"
• Canister-free oil filter element — prevents landfill, allows incineration; also eases DIY oil changes and prevents ham-fisted oil change places from "holing" or over-tightening the filter
• Very lightweight block — saves on aluminum and reduces overall vehicle weight (improving balance, too)
  • High-pressure die-cast blocks save on labor, have thinner walls, and are 20 pounds lighter than GM’s V6 blocks, saving around $40 per engine on aluminum and contributing to much lower build costs than GM’s engines.

The 3.6-liter V-6 version features high-flow intake and exhaust ports, which in combination with VVT via dual independent cam phasing, allows optimum volumetric and combustion efficiency over the full speed and load range. This results in an exceptional, flat torque curve along with high specific power. The engine’s torque exceeds 90 percent of its peak value from 1,600 to 6,400 rpm, which provides outstanding drivability and responsiveness.

In the Grand Cherokee, the engine will not have direct injection, partly because that technique, while more efficient, adds some noise and vibration. Direct injection is rumored to be on future versions of the engine.

Refinement was achieved with the help of advanced computer-aided engineering. Structural, intake, and exhaust areas deliver low levels of noise. Idle quality was improved through dual independent cam phasing.

The advanced oil filter system eliminates oil spills and contains an incinerable filter element instead of the typical spin-on filters, which are disposed of in landfill sites; the filter is conveniently located on top of the engine. The use of long-life spark plugs, regular gasoline, and a high-energy coil-on-plug ignition system also helps to reduce cost of ownership. The engine also is fully flex fuel capable, offering consumers the choice of gasoline or E85 fuel without any degradation in performance or emissions.

Type	Liquid cooled 60-degree V6
Material	Aluminum block and heads; deep-skirt block
Valves	Chain driven DOHC with 24 valves. Roller finger followers and hydraulic lash adjusters. Dual independent cam-torque actuated phasers.
Displacement	220 cid / 3.6 liters
Bore x Stroke	3.78 x 3.27 (96 x 83 mm)
Fuel injection	Returnless, sequential. Direct injection “may be coming.”
Compression	10.2:1
Fluid	6 quarts 5W20 oil; 14 quarts antifreeze; regular gas
Redline	6,400 rpm (stated elsewhere as 7,200 rpm)
Power	280 hp (209 kw) @ 6,400; 260 lb-ft (353 Nm) @ 4,800
Emission controls	Dual three-way catalytic converters, heated oxygen sensors, internal features
Assembly	First: Trenton South Engine, Trenton, Michigan

Running on regular gas, the Pentastar engine is rated for 16 mpg city, 23 highway on the Grand Cherokee — vs 16/20 for the Hemi. It meets California LEV II+ evaporative emission requirements, Tier 2, meets Federal Bin 4+ emission requirements, and Clean Fuel Fleet Certification (CCF-LEV) in all other states.

The Phoenix engine was renamed to “Pentastar” very recently, due to a hitherto unknown trademark-name conflict.

Spark plugs are installed at the end of a length tube. There is a spring running through the length of the tube, from the conventional-looking plugs up to the coils; we do not know whether the entire tube is removed, or (as we believe) the plug is removed via the spring, which is attached to the contact.

The Pentastar V6 is an interference design; it has valve reliefs but only for clearance under normal conditions. If the timing chain broke (hopefully a rare event), there could be heavy damage. (Thanks, Keith.)

The engine accessories have no brackets; they are bolted directly to the block, cutting vibration. Since the air conditioner compressor and alternator are both bolted to the block, a tensioner is used with the serpentine belt to maintain appropriate tension.

The Phoenix engine was designed to be used in a North-South and East-West configuration, depending on the vehicle.

The new state-of-the-art Trenton (Mich.) Engine South Plant will be the lead facility for production of the Pentastar V-6 engine. A duplicate, new facility in Saltillo, Mexico, will ramp up for the 2012 model year. Early production is scheduled for summer 2009 with “real” production starting in late 2009.

This report came on November 3, 2008:

A supplier (identity confirmed) reported on Chrysler’s upcoming Phoenix V6 engines, saying that they would be certain to survive any takeovers or mergers. “They’re good on mileage and power, and they’re very quiet,” said the supplier.

According to Chrysler presentations, even the most powerful Phoenix, displacing 3.6 liters and producing (in preliminary tests) over 280 horsepower, is quieter than Toyota’s 3.3 liter V6 - and far quieter than the Toyota 3.5 liter V6. Gas mileage is said to be good, partly due to the use of high-pressure, die-cast blocks, which save on labor and allow for thinner walls and less use of aluminum. These blocks are 20 pounds lighter than General Motors‘ V6 blocks, saving around $40 per engine on aluminum alone; an independent firm estimated that these engines are at least $300 cheaper to build than GM’s current V6 line, increasing the odds of its survival of a GM merger or takeover.

Chrysler wrote that: “The new Phoenix of V-6 engines will feature cylinder deactivation (MDS)...the engine will operate efficiently on three cylinders when less power is needed, and in V-6 mode when more power is needed. This optimizes fuel economy when V-6 power is not required – without sacrificing vehicle performance or capability.

“The new family of V-6 engines will feature an aluminum die cast block, dual variable valve timing (VVT) and a two-stage oil pump, among other technologies. The end result is an expected across-the-board V-6 fuel efficiency improvement of six to eight percent – in addition to new levels of V-6 power, performance and refinement.” Allpar note: the key words here are both performance and refinement!

As of July 2007, the engine was still reportedly in early-development status, but was feature-complete; ongoing work dealt with tuning, calibration, and emissions. We are certain that direct injection will be used in at least one of the Phoenix engines.

The following table was first provided in July 2006 with information from oh20, in a form not dissimilar from its current state; he updated the chart at the end of November 2008 to the following. All engines have variable valve timing unless otherwise noted.

Size	Line	Cars
3.0 V6	Base Premium Direct Injection MDS	Export models (four different varieties are apparently planned though volume will probably be low)
3.3 V6	VVT	Sebring, Avenger, Minivans
3.3 V6	Direct Injection	Challenger, Charger, Minivans, Grand Cherokee, Durango, Aspen
3.3 V6	DI/HEV	Sebring, Avenger, 300, Minivans
3.3 V6	MDS	Sebring, Avenger, Minivans
3.6 V6	VVT	Multiple models (first on Grand Cherokee)
3.6 V6	Direct Injection	Ram, Wrangler (Since the noise will be acceptable)
3.6 V6	MDS (late intro)	Challenger, Charger, 300, Minivans, Grand Cherokee, Durango, Aspen
3.6 V6	HEV	Minivans
3.6 V6	PZEV	Sebring, Avenger, Minivans
4.0 V6	Base (no VVT)	marine use
4.0 V6	Premium, MDS, no VVT	marine use
4.7 V8	VVT	Ram, Charger, 300, Dakota, Grand Cherokee, Durango, Aspen

Chrysler has announced details, including the investment in plants ($2 billion, not including engineering of the engines themselves) and the fact that Mercedes will share the basic engine architecture. The Phoenix engines, long discussed on Allpar's news and rumors forum, will be made in Mexico, Kenosha (Wisconsin), and Trenton (Michigan), with parts machined in Toledo, Ohio. Allpar at least is happy that development of these engines appears to be centered in the US though no doubt Mercedes will get most of the credit for their success.

The old Trenton Engine plant will close in 2014; the new Trenton Engine plant will open in time for the 2010 model year.

At the latest, the current V6 engines (dating back to around 1990) will be phased out in 2013, except for the 3.8 and 4.0 V6, which should finished by 2014.

Dieter Zetsche said the new engine family would operate on a modular base. The world's best V6 engines were benchmarked; and Mercedes has a camless design that may be integrated into Auburn Hills’ work. The engines will be built on flexible assembly lines that will allow the mix to be changed quickly and easily. Plants will have job rules that include 10 hour four-day work weeks and two job classifications.

The Phoenix engines were first discussed by "superduckie" way back in March 2006. oh20 (who has been accurate on the Ram, Challenger, Caliber, and Sebring) provided a table of the engines and cars they’d go into back in July 2006.

Production details

• TB007 wrote: “The mystery item behind the oil filter is probably an oil to water oil cooler. The engines do not seem to have exhaust manifolds, but rather the head is cast with an exhaust flange to one side.”
• An investment of $730 million for a new plant in Trenton, Mich., to produce the "Phoenix" family of V-6 engines. The new Trenton plant, located adjacent to the existing Trenton Engine Plant, will have an annual capacity of 440,000 engines and is expected to begin production in 2009. The Phoenix family of engines is the first of these initiatives that will go into production. In the long term, the Phoenix engines will replace the current four V-6 engines.
• An investment of $700 million to build a new axle plant in Marysville, Mich. The facility will create a new family of axles that provide better fuel economy. In addition, the common axle family will enable the company to consolidate the number of axles for better economies of scale. This plant will be run by ZF.

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