When Chrysler announced it was bringing back the legendary Hemi in the early 2000s, it was a big deal. This new series of Hemi engines is often referred to as the “Gen. 3” after the first generation FirePower (1951-59) and second generation Elephant 426 (1964-71).
Note: This Spec Guide is part of a series of Hemi Engine Spec guides we’re putting together. See Other Hemi Engine Spec Guides Here.
Bigger is Better: Meet the 6.4L Gen. III Hemi Apache
This engine plays off of a historical aspect of one of the early Gen. I Hemi 392 cubic inch engines introduced in 1957. Developed under code name “Apache,” this Gen. III version first appeared in 2011 and offers increased displacement and power over the previous 6.1L Hemi with a longer stroke. This engine also carries the BGE casting mark on the block that stands for Big Gas Engine that is used in a number of different vehicles, from the Dodge Challenger to medium duty Ram trucks.
The larger truck 6.4L engines use a lower 10.0:1 compression compared to the passenger cars and SUVs that sport 10.9:1 compression, and this higher squeeze helps make as much as 485 hp and 475 lb.-ft. of torque. That’s outstanding horsepower for a normally aspirated production engine that will make serious power well past 150,000 miles (and be fully emissions compatible).
This Guide is for the 2011+ Mopar Gen. III 6.4L Apache Hemi
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2011+ Mopar Gen. III 6.4L Apache Hemi Performance & Applications
| Year | Model | Horsepower | Torque (ft.-lbs.) |
|---|---|---|---|
| 2011-14 | Challenger SRT8 | 460 @ 6,000 RPM | 470 @ 4,200 RPM |
| 2015 | Challenger SRT8 | 485 @ 6,100 RPM | 475 @ 4,700 RPM |
| 2015 | Cherokee/Durango | 475 @ 6,000 RPM | 470 @ 4,300 RPM |
| 2014+ | Ram 2500/3500 | 366 - 410 @ 5,600 RPM | 429 @ 4,000 RPM |
2011+ Mopar Gen. III 6.4L Apache Hemi Engine Compression
| Version | Car | SUV | Ram Truck |
|---|---|---|---|
| Compression | 10.9:1 | 10.9:1 | 10.0:1 |
2011+ Mopar Gen. III 6.4L Hemi Engine Block Specs
| Mopar 6.4L Hemi Block Specs | |
|---|---|
| Casting Numbers | 5037473BE (or) 5037473BG “6.4L” |
| Material | Iron |
| Displacement | 6.4L / 391 c.i.d. |
| Bore Dia. | 4.090" |
| Stroke | 3.72" |
| Deck Height | 9.25" |
| Bore Spacing | 4.46" |
| Thrust Bearing Location | Number 3 |
| Main Cap Style | 2 Bolts with Lateral Cross-Bolts |
| Cam-to-Crank Centerline | 7.44" |
| Bellhousing Bolt Pattern | Same as Earlier Magnum LA V8 Small Block, but with Top Center Bolt Eliminated |
| Piston Squirters | Yes |
2011+ Mopar Gen. III 6.4L Hemi Engine Rotating Assembly
| Mopar 6.4L Hemi Engine Rotating Assembly Specs | |
|---|---|
| Piston Material | Hypereutectic |
| Piston Style | Slight Dome with Valve Notches (Truck is different) |
| Piston Ring Package | 1.2mm, 1.2mm, 2.0mm |
| Wrist Pin Diameter | 0.945" |
| Connecting Rod Material | Powdered Metal (Improved strength design) |
| Connecting Rod Style | I-Beam |
| Connecting Rod Length | 6.200" (Shorter than other Gen. III Hemis) |
| Connecting Rod Bearing Bore | 2.125" |
| Crankshaft Material | Forged Steel |
| Crankshaft Main Journal Dia. | 2.559" |
| Crankshaft Rod Journal Dia. | 2.126" |
| Crankshaft Reluctor Count | 58x |
| Crankshaft Mounting Flange | 8 Bolts |
2011+ Mopar Gen. III 6.4L Hemi Engine Cylinder Heads
| Mopar 6.4L Hemi Engine Cylinder Head Specs | |
|---|---|
| Casting Number | Car/SUV 5037369BD (or) 68166435AA-A02 Truck 05045468AE (and) 68166435AA, AB, AC, AD |
| Cylinder Head Material | 356 T6 Aluminum |
| Combustion Chamber | 74cc |
| Intake Port Shape | Square |
| Exhaust Port Shape | "D" Shaped |
| Intake Valve Diameter | 2.14" |
| Intake Valve Design | Hollow Stem |
| Exhaust Valve Diameter | 1.65" |
| Exhaust Valve Design | Hollow Stem, Sodium Filled |
| Cylinder Head Bolt Style | Torque to Yield (TTY) |
| Cylinder Head Bolt Size | M12 x 1.5mm & 8mm |
| Spark Plug | 14mm, Gasket, 1.043" Reach, Projected Nose, 5/8" hex |
2011+ Mopar Gen. III 6.4L Hemi Apache Engine Cam Specs
| Mopar 6.4L Hemi Engine Camshaft Specs | |
|---|---|
| Duration @ 0.050" (Intake/Exhaust) | 221° / 225° |
| Lobe Separation Angle | 114° |
| Valve Lift (Intake/Exhaust) | 0.571" / 0.536" |
| Multiple Displacement System (MDS)? | Only In Vehicles w/Automatic Transmission |
| Variable Cam Timing (VCT)? | Yes |
| Cam Journal Dia. | 57mm Front (Note: Smaller to the rear.) |
2011+ Mopar Gen. III 6.4L Hemi Engine Valvetrain Specs
| Mopar 6.4L Hemi Valvetrain Specs | |
|---|---|
| Lifter Design | Hydraulic |
| Lifter Retainer | Plastic Holder |
| Lifter Body Diameter | 0.842" |
| Rocker Arm Mounting Style | Shaft |
| Rocker Arm Style | Die Cast, Roller Fulcrum |
| Rocker Ratio | 1.60:1 (Intake) 1.66:1 (Exhaust) |
| Valve Spring Style | Beehive |
| Valve Angle | 18° (Intake) 16.5° (Exhaust) |
| Timing Chain Guide Style | Spring-Loaded Tensioner |
Other Key 2011+ Gen. III 6.4L Hemi Engine Specs
| 6.4L Hemi Throttle Body, Fuel Injectors, Oil Pan & More | |
|---|---|
| Intake Manifold | Composite “Active” with variable length |
| Throttle Body | 80mm, 4-Bolt |
| Throttle Control | Electronic |
| Fuel Injector Flow | Car/SUV 27 lb./hr. @ 58 PSI MD/HD Truck 31 lb./hr. @ 58 PSI |
| Flex Fuel Capable | No |
| Fuel Injector Connector | USCAR, EV6 |
| PCM | GPEC2 (or) GPEC2A |
| Crankshaft Reluctor Ring | 58x |
| Camshaft Sensor Location | Passenger Side, Front |
| Oil Pump | Gerotor |
| Variable Cam Timing (VVT) | Yes |
| Firing Order | 1-8-4-3-6-5-7-2 |
| Total Weight, Full Dress | 582 lbs. |
Greetings!
Refer to the engine specs within article “2011+ Mopar Gen. III 6.4L/392 Hemi”. The stated con rod BE bore of 2.125″ indicates a crank rod journal of 2.000″, not 2.126″.
Please investigate; thank you.
Don
“Duck”
Hi i’m confused one article says hemi heads 6.4L 2018 and up has heads made of T356 aluminum and 2011-2017 has T319 and another says 2011 and up has T356. How can i be sure i’ve got the T356 heads.Thank You Charles
Cam specs listed at 0.050 lift are incorrect in this article.
The stock cam numbers @0.050″ lobe lift I am finding for the non-MDS 6.4 HEMI camshaft (MOPAR PN#: 5037379BC) are:
Stock LSA = 121° LSA
Stock Intake/Exhaust “Valve” Lift = 0.574″/0.541″ (close to your numbers)
Stock Intake/Exhaust Duration @0.050″ “Lobe” Lift = 215°/221° (duration is way off)
The I expect it is possible to have duration of 286/288 @0.006″ lobe lift.
Hey Mike, thanks for the heads up: we made some updates based on the specs found here.
Just curious of what the stock cam power range is on the 2018 6.4L (392 SRT) R/T Scat Pack Challenger? It appears to redline at 6400RPM…..is it 4000 to 6100?
Please confirm when you have a free moment. Thanks.
Stock tune the torque curve has a huge dip around 4600. It is caused by the variable length intake runner shortening up a little too soon.
The cam duration numbers @ .050 is wrong.
Would love to read the right @50 cam specs …..
Definitely wrong. Thanks for tagging this. Otherwise, this is a great reference.
Hey thanks guys, we made some updates in the chart above.
Maybe someone can chime in with the right info? I only read specs about the 6 speed NON MDS cam …., so I assume the AUT. cam has different specs….? Can someone second that? And maybe come up with those specs..?
THANKS IN ADVANCE…
Are the BE and the BG castings on the 6.4 still both considered the “Big gas Engine” ??
I’ve been back and forth with a friend on this I believe they are both the same
I have a 70 AMX that I am in the beginning stages of restoring. I was planning on putting in a 5.7L Hemi with an automatic transmission.
One thing I was looking for and found your website was headers. How do you find a set of headers for a 5.7L Hemi for a 1970 AMX? I don’t feel comfortable making my own with the kits they sell.
And I was going to forgo the computer control and go old school distributor with an MSD ignition. I am old school and I don’t know anything about these computers so I guess I was just going to go with what I know.
Thanks for any help and guidance.
Hey Dale, click here to see a few dozen header options for the Gen 3 Hemi 5.7L. I’m not sure if they’ll fit your AMX though–I recall the early days of LS Swaps, folks would get the shorty style headers, then fab up the header-back system. Perhaps that’s an easier option that fabbing headers?
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In regard to your follow up questions, you might want to read these articles. You didn’t mention driveline, but it seems like you may want to secure the factory harness and transmission (with controller) too, to make it all work.
* Gen. III Hemi-Swapped AMC Javelin
* This Guy Stuffed a Gen. III Hemi Into a 1951 Kaiser Henry J
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You can also call the Summit Racing tech folks. They’ve got a ton of knowledge about the swap, and can help walk you through some specifics. Hope this helps, sounds like a cool project!