A popular topic about 440 Six Packs is what kind of camshaft it had from the factory. Let’s answer, what was the stock 440 Six Pack cam specs?
The 440 Six Pack camshaft specs are a .450″ intake lift and .458″ exhaust lift. The duration is 268° intake and 284° exhaust. The durations @ .050 are 208° intake and 221° exhaust. The lobe separation angle is 115° and the valve overlap is 46°.
This article will explain any differences between the years of the production run. In addition, I’ll include information like bolts, lifters, bearings and valve timing.
Stock 440 Six Pack Cam Specs
The following table contains the 440 Six Pack cam specs for all three years plus what the service manual states in 1972.
|Duration @ .050″||208°in./221°ex.||208°in./221°ex.||208°in./221°ex.||208°in./221°ex.|
|Lobe Separation Angle||115°||115°||115°||115°|
|Intake Lobe Centerline||113° (ATC)||113° (ATC)||113° (ATC)||113° (ATC)|
|Exhaust Lobe Centerline||117° (BTC)||117° (BTC)||117° (BTC)||117° (BTC)|
|Intake Opens (BTC)||21°||21°||21°||21°|
|Intake Closes (ABC)||67°||67°||67°||67°|
|Exhaust Opens (BBC)||79°||79°||79°||79°|
|Exhaust Closes (ATC)||25°||25°||25°||25°|
|Cam Bolts||1 bolt||3 bolts||3 bolts||3 bolts|
We now know a few factory Six Pack cars made it off the assembly line in ’72. To my surprise the horsepower numbers were the same as 1971. Read about them in my article, Cars With a 440 Six Pack From the Factory.
Six Pack (Dodge) and Six Barrel (Plymouth) engines were exactly the same except for the decals and badging.
Some early 1969 literature in a few magazines indicated slightly more aggressive specs than what was actually used. This often produces some discrepancies in the cam specs.
Willem Weertman confirms the cam specs in his book, Chrysler Engines, 1922-1998.
The Six Pack engine used a host of performance parts from the A134 engine (440 HP), including the long-duration 268-284-46 camshaft.
Low Taper Spec
The Six Pack and 6-BBL engines came with the Hemi valve springs. Due to durability testing with the stiffer valve springs, the Six Pack cams have a low taper design allowing the lifter to rotate in the bore.
This is where the Six Pack cam differs from a Magnum engine.
Camshaft Journals and Bearings
Cam Journal Diameters
- No. 1: 1.998″-1.999″
- No. 2: 1.982″-1.983″
- No. 3: 1.967″-1.968″
- No. 4: 1.951″-1.952″
- No. 5: 1.748″-1.749″
- Material: Steel backed babbitt
- Number: 5
- Diametral Clearance: .001″-.003″
- Maximum allowable before reconditioning: .005″
- No. 1: 2.000″-2.001″
- No. 2: 1.984″-1.985″
- No. 3: 1.969″-1.970″
- No. 4: 1.953″-1.954″
- No. 5: 1.750″-1.751″
More Mopar Engine Cam Articles
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I first learned about 440 Six-Pack cam specs in 1984 when I was building my first 440 engine. I wanted a more aggressive cam than the factory. I ended up using a Crane cam which had a .504″/.528″ lift.
I’ve been researching Mopars and the 440 Six Pack engines for approximately 40 years. My research includes personal experience, books, manuals, articles, magazines, webinars, live events and videos.
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