Degreeing the cam question ??

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Brooks James

Brooks James

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I got a $150 "core" 1994 360 magnum.
It has a fairly new valve job and new springs, retainers, and locks. The camshaft in it sounded good on a sound clip I heard
.I thought that I was measure everything before I tore the motor down.


I borrowed a cam degree kit. No instructions.
I know lift can be measured , what about duration ??

Looking now for camshaft degreeing for dummies instructions
 
After you find absolute TDC and get your degree wheel mounted and a pointer set at TDC you calculate your duration from lift. If you have a hydraulic cam, roll the engine over until the lifter reads .006 lift and read the degree wheel. Then go to .020 lift and read the degree wheel. Then .050 and so on. Once you reach max lift and start down the closing side, take readings at all the lift points you did on the way up. Then it’s simple math.

You .006-.006 readings are the advertised duration for most hydraulic lobes. Then you have your @.020, .050 and whatever other lifts you measured durations.
 
Do you have an adjustable cam sprocket or crankshaft sprocket? If not about all you can do is to verify the cam is at advertised specs. If it's not you'll have to buy some adjustable parts to make it so. What brand is the cam? should be a serial number on it somewhere, you can call the manufacturer and get a cam card sent to you.
 
Brooks James said:
I got a $150 "core" 1994 360 magnum.
It has a fairly new valve job and new springs, retainers, and locks. The camshaft in it sounded good on a sound clip I heard
.I thought that I was measure everything before I tore the motor down.


I borrowed a cam degree kit. No instructions.
I know lift can be measured , what about duration ??

Looking now for camshaft degreeing for dummies instructions
Click to expand...
1st of all hopefully the heads aren't cracked as 99.9% of factory magnum heads are cracked right between the seats.
 
Post #2 is absolutely 100 and 50 million percent correct. If you do not find true TDC nothing will be correct. You must must MUST have that baseline.
 
RockinRobin said:
Do you have an adjustable cam sprocket or crankshaft sprocket? If not about all you can do is to verify the cam is at advertised specs. If it's not you'll have to buy some adjustable parts to make it so. What brand is the cam? should be a serial number on it somewhere, you can call the manufacturer and get a cam card sent to you.
Click to expand...
The cam was a backdoor deal from a guy that had worked for Crane Cams.

MOPARMAGA said:
1st of all hopefully the heads aren't cracked as 99.9% of factory magnum heads are cracked right between the seats.
Click to expand...
Have read of and seen others run with the tiny cracks, no problem
 
RockinRobin said:
Do you have an adjustable cam sprocket or crankshaft sprocket? If not about all you can do is to verify the cam is at advertised specs. If it's not you'll have to buy some adjustable parts to make it so. What brand is the cam? should be a serial number on it somewhere, you can call the manufacturer and get a cam card sent to you.
Click to expand...
No adjustable sprocket, plan on one for this motor build
 
So this is a $150 engine that has had a top end refresh?

I would say there is no reason to degree the cam, except for these reasons:
- you want to learn how to degree cams
- somebody you know has installed the same cam in the same engine, & had it dyno tested for max HP with the cam in different installed positions.


Unless you have data/info of how this cam performed in a similar engine, there is no way of knowing whether best power would be made with the cam installed straight up, advanced, or retarded.
 
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