Chrysler Group's New 4.0-liter V-6

The Chrsler Group has a new 4.0-liter V-6 that will be the most powerful naturally aspirated V-6 in their lineup. The 4.0-liter V-6 produces 255 hp @ 6,000 rpm and 265 lb-ft of torque @ 4,200 rpm. More than 10 engine characteristics were designed specifically for minimal engine noise, and to ensure that the sound would remain pleasing to the driver. The result is an engine with equal or better noise, vibration and harshness (NVH) qualities than competitive benchmark engines. The 4.0-liter will be available in the 2007 Chrysler Pacifica and Dodge Nitro.
Full Press Release and engine specs after the jump...
Auburn Hills Mich, Jun 22, 2006 -
The leading goals guiding the development of the new Chrysler Group 4.0-liter SOHC V-6 were impressive low-rpm torque and extremely smooth and quiet operation.
"When we decided to create a more powerful V-6 for Chrysler Group vehicles, we invested in building on the dependable 3.5-liter V-6," said Bob Lee, Vice President, Chrysler Group Powertrain. "The new 4.0-liter V-6 delivers more power than any naturally aspirated V-6 engine in our vehicles, and does so with world-class smoothness and refinement."
The new engine has impressive low-rpm torque that will give customers very good engine response around town and provide the power they expect from a world-class V-6. The 4.0-liter V-6 produces 255 hp @ 6,000 rpm and 265 lb-ft of torque @ 4,200 rpm. The engine produced 15 more lb-ft of torque at peak power rpm, and as much as 35 lb-ft more torque throughout the power curve.
Specific changes from the 3.5-liter engine for improved power include:
* Crankshaft stroke increased from 2.47 in. (81 mm) to 2.78 in. (91mm)
* Displacement changed from 214.7 cu. in. (3.518 liters) to 241.2 cu. in. (3.952 liters)
* New camshaft profile featuring higher lift and revised timing events
* New upper intake manifold with improved flow
* Compression ratio raised from 10.0:1 to 10.2:1
Equally important are the decreases in engine noise, vibration and harshness (NVH). More than 10 engine characteristics were designed specifically for minimal engine noise, and to ensure that the sound would remain pleasing to the driver. The result is an engine with equal or better NVH qualities than competitive benchmark engines.
Specific changes from the 3.5-liter engine for decreased NVH include:
* Increased main-bearing width and diameter
* Tighter crankshaft balance spec
* Select-fit rod bearings
* Reduced reciprocating mass piston assemblies
* Added ribbing to the sides of the engine block
* Increased pan-rail thickness on block
* Direct-mount oil pan to transmission bell housing
* Thermoplastic valve cover
* New "low rumble" intake manifold
* Intake lobes splayed
* Equal length exhaust
The 4.0-liter V-6 utilizes an semi-permanent mold cast aluminum block with iron liners and cast-aluminum cylinder heads. It is a single overhead camshaft (SOHC), 24-valve engine. The engine is produced at the Trenton Engine Plant in Trenton, Mich., and will debut first in the 2007 Chrysler Pacifica, followed later this year by the 2007 Dodge Nitro.
4.0-liter SOHC, 24-valve V-6
Description: The 4.0-liter is a new engine, based on our 3.5-liter V-6.
Type and Description____________________60-degree V-6
Displacement__________________________241 cu. in. (3952 cc)
Bore x Stroke__________________________2.78 x 3.58 in. (96x91 mm)
Valve System__________________________ 24-valve, single overhead camshaft
Fuel Injection__________________________Sequential, multi-port, electronic
Construction___________________________Semi-permanent-mold cast-aluminum block with iron liners
and cast-aluminum cylinder heads
Compression Ratio______________________10.2:1
Power (SAE net)________________________255 (190kw) @ 6,000 rpm
Torque (SAE net)_______________________ 265 (360 N•m) @ 4,200 rpm
Max. Engine Speed_____________________6,200 rpm
Fuel Requirement______________________Unleaded mid-grade, 89 octane (R+M)/2 preferred
Unleaded regular, 87 octane (R+M)/2 acceptable
Oil Capacity___________________________5.5 qt. (5.2L) with dry filter
Production Facility______________________Trenton Engine Plant, Trenton, Mich.
Customer benefits: Significant changes were made for improved power and reduced noise, vibration and harshness.
Availability: 2007 Chrysler Pacifica and Dodge Nitro
4.0 dodge V-6 engine Chrysler Mercede NHV


