Yanked a bad cam from a 1978 Dodge Magnum w/360, looks to be a Comp Cams 280H (Magnum series) One lobe about gone. That’s bad enough but, we now know why this nearly 4000lb car with nothing more than a Street Demon carb, dual exhaust, stock lockup torque converter and 2.45 gearing was a complete dog when we bought it and no matter what we did for tuning it was the same. Even afterwards with the addition of a 3.21 gear and a looser converter it still was not enough. Waaay too much cam, installed dot to dot! Was told it was an Erson cam but regardless, another example of someone not matching cam selection with everything else. Not to worry, a better matched smallest Lunati Voodoo is taking its place. Should be a major improvement!
Disappearing Cam Lobe
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pishta
I know I'm right....
We found the same rear transplanted in a 170 64 Dart. Talk about a dog, that thing could barely make it up an inclined driveway. We put a 225 in it thinking the motor was tired, but it didn't help a helluva lot. With that tall cam, I doubt it would holeshot a wheelchair across an intersection.
512Stroker
We are all here because we are not all there.
I think you may have a Comp Cam on your hands, hence the CC overlapped stamping.
I have seen that before where it just flattens out one or two lobes off the cam.
I always thought that it may be caused by a tight lifter bore not allowing the lifter to rotate.
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yellow rose
Overnight Sensation
This is my sons car, so I only see the car sporadically (but I get the pleasure of diagnosing and leading the work performed as needed) I’d say this started a quite a few months ago where I noticed the dreaded lifter clack. Only got more pronounced and at first I was thinking lifter or rocker arm. The young man has been using 20w-50 turns out.....I believe he now understands why that is not a good grade to run!
20w-50 is fine for summer type climate... Too much spring pressure, or not enough lubrication (additive) may be the cause...
It's Magnum series cam so it has to work in a Dodge Magnum.
Worn cam plate or a cheap top gear changes the position of the cam lobes to lifter bore. When the are centered the lifters don't spin. resulting in the lobe wearing off. When ever you are building a motor lifter bore position is critical with tappet cams. Rollers don't matter as much. You have a bad lobe find the reason on tear down. Its not always the cams fault.
No idea who put this cam in or how many miles on it prior to my son buying it. Stuck in straight up using a stock timing chain. Cam bearings, cam plate, chain and gears, positioning etc all looked upon visual inspection good. Been running for almost three years and around 10,000 miles at most until the clack started. Just one lobe and lifter gone, the rest, lifters especially, are in great shape. Looks to have been spinning in its bore as the lifter face is nicely polished and concave. The bright side is having a good reason to put a correctly spec’d cam in there to compliment the setup.
Wyrmrider
Well-Known Member
Use a HR cam with the stock lifters under 6500 rpm, beehive springs and light retainers- what's not to like
screw these predicted failures comp cam or erson does not matter - Wrong chevy cam for your needs
I like that lunati but why HFT Degree your cam in what springs ??
put a stripe on your pushrods and rotate the motor (after spinning the oil pump- and see if they rotate
do not add anything to a SN oil- it makes EP worse- in addition the high detergent washes the EP off
get an oil for the flat tappet cam from a blender who formulates the EP in
screw these predicted failures comp cam or erson does not matter - Wrong chevy cam for your needs
I like that lunati but why HFT Degree your cam in what springs ??
put a stripe on your pushrods and rotate the motor (after spinning the oil pump- and see if they rotate
do not add anything to a SN oil- it makes EP worse- in addition the high detergent washes the EP off
get an oil for the flat tappet cam from a blender who formulates the EP in
That's pretty gnarly.
I can appreciate all you’ve posted here
as well I’m sure many others, my son not so much. Young working man paying off college loans, living on his own with a dad that helps him on his Mopar. Cams and technical things...Roller conversion, beehive etc just not an option in his world. No money for (in this case) other extravagance. Unfortunately for me he isn’t immersed in Mopar or car forums and how it all works, just likes old cars that sound good and are fun to drive so we works with what’s we gots
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