How to ID a used cam ?
#289567
04/15/09 09:37 PM
04/15/09 09:37 PM
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Joined: May 2004
Posts: 1,522 Ste-Sophie, Quebec, Canada
Wedgeman
OP
pro stock
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OP
pro stock
Joined: May 2004
Posts: 1,522
Ste-Sophie, Quebec, Canada
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HI guys... Got a cam from a fellow enthousiast here on Moparts, he did not know the exact specs of it.
Now how can I identify the cam and the specs..There are engraved numbers and stamped numbers at the end of the stick.....like so:
engraved E 3312 HR 12 stamped 960084
Can you help ? it a 5.9l magnum roller cam
Dan
Last edited by Wedgeman; 04/16/09 05:26 PM.
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Re: How to ID a used cam ?
[Re: Wedgeman]
#289568
04/15/09 11:56 PM
04/15/09 11:56 PM
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Joined: Oct 2003
Posts: 21,345 Marysville, O-H-I-O
70Cuda383
Too Many Posts
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Too Many Posts
Joined: Oct 2003
Posts: 21,345
Marysville, O-H-I-O
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I would think that once you figure out who made the cam, they will be able to look up those numbers for you.
some machine shops have a cam profiler that will measure the lobes and tell you what the specs are
**Photobucket sucks**
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Re: How to ID a used cam ?
[Re: 70Cuda383]
#289569
04/16/09 12:44 AM
04/16/09 12:44 AM
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Joined: Jun 2004
Posts: 893 Tustin, CA
pishta
super stock
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super stock
Joined: Jun 2004
Posts: 893
Tustin, CA
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Chuck it up in some V blocks and put a dial indicator on it and a degree wheel on the end. Set your marker and dial indicator to zero on the backside of the lobe and start to turn it slowly. Watch until the D.I. hits .050 lift and then note the degree on the marker. Continue to turn until it tops out for lift in inches (do some math with your rocker ratio to find valve lift) turn until the D.I returns to .050 on the backside and then determine the degrees past. You got your duration. Valve centerline is determined from som e lobe centerline, usually around 112-118 degrees from some other point (maybe between the intake and exhaust lobes?) that I dont know. Duration is measured differently from cam manufacturers. Mopar measures them from some weird number, many measure from .050 and some measure from initial valve lift, so you can get a 312 or a 250 from the same cam depending where you start to measure duration. Eg. [Email]250@.050[/Email] is lumpy, and Demon rates their carbs on this cam spec on weather it is a street Demon (lower than 250) or race demon (over 250) performance level. Has to do alot with vacuum requirements. Rollers have a fast ramp rate. Nice for a long duration at a low lift.
Last edited by pishta; 04/16/09 12:46 AM.
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Re: How to ID a used cam ?
[Re: pishta]
#289570
04/16/09 03:47 AM
04/16/09 03:47 AM
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Joined: Oct 2003
Posts: 21,345 Marysville, O-H-I-O
70Cuda383
Too Many Posts
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Too Many Posts
Joined: Oct 2003
Posts: 21,345
Marysville, O-H-I-O
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well, that would work too, but isnt the lift calculated WITH the rocker ratio? so if the cam lobe has "lifted the lifter" by .050" then wouldn't the valve actually be .35"? (magnum motors have a 1:7 rocker ratio)
so for .050 lift you actually want .007 lift at the cam lobe.
and yes, it's true that cam manufacturers advertise different numbers for duration, but just about all of them list the actual duration from .050 to .050.
so my comp XE275HL, comp lists the intake duration at 275 degrees, but lists the @ .050 duration to be something like 235
**Photobucket sucks**
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Re: How to ID a used cam ?
[Re: Wedgeman]
#289577
04/18/09 02:38 PM
04/18/09 02:38 PM
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Joined: Nov 2003
Posts: 36,040 Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
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Quote:
engraved E 3312 HR 12 stamped 960084 it a 5.9l magnum roller cam
I'd email a half dozen of the major cam companies & ask them if those #'s belong to their stuff
Last edited by RapidRobert; 04/18/09 02:38 PM.
live every 24 hour block of time like it's your last day on earth
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