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OEM specs for ORIGINAL Chrysler Marine 440 Camshaft

stevel3007

New member
All,

I'm looking for any documentation/knowledge on the camshaft profile for the original marine engines. The service manual has nothing.

I'm in the process of "degree'g the cam" on both my engines (results to follow) as part of my rebuild/overhaul but I'm looking for a baseline to compare the results to.

Any pointers to a "cam card" of the original OEM camshaft?

Thx
Steve
 
I think I'd draft a form letter and send it to several cam grind companies to their tech support. I would think they have the specs if they grind replacements. Other than that one could indicate the cam on V-blocks with a degree wheel attached. The standard rocker is 1-1/2 the lift.
I'd be curious if it comes close to any of these in the "Updated" area.......

Mopar Engine Cam Chart (mopar1.us)
 
I think I'd draft a form letter and send it to several cam grind companies to their tech support. I would think they have the specs if they grind replacements. Other than that one could indicate the cam on V-blocks with a degree wheel attached. The standard rocker is 1-1/2 the lift.
I'd be curious if it comes close to any of these in the "Updated" area.......

So here's is what I measured on my cam. Full disclosure here; this is the first time I did this procedure (albeit after watching at least a dozen Youtube videos) so consider the data "suspect"... I took my measurements on #1 cylinder and also ran a quick set on the #4 cylinder as a reality check - and the results were quite close.

As suggested above, next step is I'll check in w a few cam manufacturers to see what they can do for a replacement. Not sure I'll replace it but let's see how it runs after I finish the rebuild. I'm wondering if there is a more optimal cam for a sub-3000 RPM 42' 15 ton 10 knot boat? Better fuel economy would be nice but I'm not sure that is realistic. Anyway, FYI.

- assume 70’s era cam (engine is 1977) but unclear if it is stock Mopar or not
- using hydraulic flat tappets
- for standard rotation [starboard] engine

#1 Cylinder Intake

Max tappet lift 0.286”
Valve lift 0.429” (using 1.5 rocker ratio)
Cam baseline run out 0.0” (no deviations off 0)

Opens @ 0.006” 15 deg BTDC
Closes @ 0.006” 73 deg ABDC
Duration @ 0.006” 268 deg

Centerline Below Max 0.020” 086 deg
Centerline After Max 0.020” 144 deg
Centerline calculation 111 deg ATDC (crank)

#1 Exhaust

Max tappet lift 0.303”
Valve lift 0.455” (using 1.5 rocker ratio)
cam baseline run out 0.0”

Opens @ 0.006” 75 deg BBDC
Closes @ 0.006” 51 deg ATDC
Duration @ 0.006” 306 deg

Centerline Below Max @ 0.020” 216 deg (on the wheel ATDC)
Centerline After Max @ 0.020” 274 deg (ATDC)
Centerline calculation 245 deg ATDC = 115 deg BTDC (crank)

Lobe separation = 111 + 115 = 226 deg (crank) = 113 cam deg


#4 Cylinder (for confirmation of above measurements on #1)
Intake
Max tappet lift 0.287”
Valve lift 0.431” (using 1.5 rocker ratio)
Cam baseline run out 0.0”

Opens @ 0.006” 15 deg BTDC
Closes @ 0.006” 75 deg ABDC

#4 Exhaust
Max tappet lift 0.301”
Valve lift 0.452” (using 1.5 rocker ratio)
Cam baseline run out 0.0”

Opens @ 0.006” 74 deg BBDC
Closes @ 0.006” 55 deg ATDC
 
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