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Defective NEW camshaft. Ever seen one like this?

I once received a MP purple shaft thru the mail broken in half , or maybe it was for 2, 4 cylinders !
 
I've installed two Comp Cams in the past couple years and they both looked like that. Lesson 1: don't apply assembly lube with your palm unless you like getting cut up. The casting roughness is a nuisance but if the roughness is not on the lifter contact surface, it will be okay. Of course...both of those Comp Cams wiped out during break-in even though I did everything by the book. I've given up on comp Cams and have had no problems with other cam makers.
 
Uhh, did it occur to you that the reason the cams went bad is directly because of the roughness? The lifters sit off center of the lobes, hanging toward that rough edge. Guess what happens? The edge runs against the foot of each lifter, shaving the edge off while chipping away at the lifter.
 
What everyone is missing here is the rough edge doesnt protrude above the cam lobe surface. It cant touch a concave lifter. This casting roughness would have zero to do with cam failure. Is it pretty? No. But it's just like any other casting flash in the motor. Deburr it. Lifters not rotating, sloppy or poorly finished lifter bores, excessive spring pressure, wrong oil, wrong break in procedure. Theses are what you should be worried about. Not the fact that the casting isnt zoomy looking. How many of you remove sharp edges from rods, rod caps, pistons, piston oil holes, ends of valve spring coils, etc? I'll bet not many.
Doug
 
What everyone is missing here is the rough edge doesnt protrude above the cam lobe surface. It cant touch a concave lifter. This casting roughness would have zero to do with cam failure. Is it pretty? No. But it's just like any other casting flash in the motor. Deburr it. Lifters not rotating, sloppy or poorly finished lifter bores, excessive spring pressure, wrong oil, wrong break in procedure. Theses are what you should be worried about. Not the fact that the casting isnt zoomy looking. How many of you remove sharp edges from rods, rod caps, pistons, piston oil holes, ends of valve spring coils, etc? I'll bet not many.
Doug
Op's pics showed that the rough edges did appear to protrude above the normal cam surface.
 
Op's pics showed that the rough edges did appear to protrude above the normal cam surface.
The machining would have removed them. A cam tolerance is in .000x". How could .0xx" nubs still protrude above the lobe? Not happening.
Doug
 
The machining would have removed them. A cam tolerance is in .000x". How could .0xx" nubs still protrude above the lobe? Not happening.
Doug
Well, if it did happen, it would be a defect.
 
What everyone is missing here is the rough edge doesnt protrude above the cam lobe surface. It cant touch a concave lifter. This casting roughness would have zero to do with cam failure. Is it pretty? No. But it's just like any other casting flash in the motor. Deburr it. Lifters not rotating, sloppy or poorly finished lifter bores, excessive spring pressure, wrong oil, wrong break in procedure. Theses are what you should be worried about. Not the fact that the casting isnt zoomy looking. How many of you remove sharp edges from rods, rod caps, pistons, piston oil holes, ends of valve spring coils, etc? I'll bet not many.
Doug
In 7 of the lobes, there was a sharp edge sticking above the machined surface. It was like a narrow strip of grass left UNmowed at the edge. Three counter people at Summit Racing in Sparks, Nevada yesterday looked at it with amazement. Yeah, the lifters on these 7 lobes would have made contact since the sharp edges were higher than the .004 convex of the lifters. Yeah, lifters are CONVEX, not concave.
The Summit people apologized and were not surprised when I politely declined their offer to exchange it for another Comp Cam!
 
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A late friend used to build engines for his late model and modified dirt cars. Years ago he stoped using anything made by Comp Cams. Said they were crap.
He also said the quality of Lunati cams dropped after the takeover by Holley.
He liked Erson, Bullet and Howards.
 
You can try Engle also. They make grinds for the 904 lifter. Hughes used/uses them for their proprietary cams. I believe they are still located in the PRC[ peoples republic of California].
 
In 7 of the lobes, there was a sharp edge sticking above the machined surface. It was like a narrow strip of grass left UNmowed at the edge. Three counter people at Summit Racing in Sparks, Nevada yesterday looked at it with amazement. Yeah, the lifters on these 7 lobes would have made contact since the sharp edges were higher than the .004 convex of the lifters. Yeah, lifters are CONVEX, not concave.
The Summit people apologized and were not surprised when I politely declined their offer to exchange it for another Comp Cam!

So you returned it, good they understood you refused an exchange.
Although you already confirmed it would have touched the lifter as is, if it would not have now i wondered it would have started to contact later after the break-in as i guess you do loose some material during this time.
Then after a succesfull break-in you could have still ended up with failure.

If it looks nice or not doesn't matter, i don't understand why they even took the chance of leaving that edge there, yes it will be an additional step in production and adds costs, but a company like them should know that this i quite critical and get them edges de-burred prior to calling it a finished product.
That's why it makes me wonder, was this a product that was not ready and got accidentally boxed or is this their standard now days?
I had a look at my Dbilas dynamic camshaft i received for my other project (non Mopar) and found the edges de-burred properly.
 
I posted about this on a couple other forums. On Saturday, a VP from Comp Cams sent me a PM. He apologized and offered to make it right. I responded....I told him that I understand that things happen and that I didn't post about it to get freebies. I thanked him and told him that I did appreciate that he made the effort to settle the matter.
 
I've got a thread on here somewheres where I swapped out a cam in a previous 440 in Fred
with the Comp 268 cam (recommended by several of you folks).
Judicious, copious amounts of Comp brand break-in products were used along with Brad Penn
"green", lots of ZDDP, all that jazz.
Damn thing wiped two lobes in short order....barely made it a couple hundred miles out of
break-in.

That's the second Comp cam I've had do that. No, I'm not expert enough to tell you if it was
a lifter caused issue or the cams themselves, but both of them were similar to what Greg describes
here - very sharp edges on the lobes, razor sharp enough that I did lightly polish the edges with
some emery cloth to try and settle them down a little - to no avail.

The old purple shaft (484, apparently Greg's favorite :) ) in Fred's current 440 gives me the little
bit of lope but pulls when needed, so I'm fine with it after probably 5-600 miles now.
 
The MP cams of old were done by Racer Brown.
That's what I remember from Direct Connection days of yore - Mopar performance cams were either purpleshaft
series or the more aggressive Racer Brown's.
That IS the same Racer Brown you guys are talking about today, right?
 
That's what I remember from Direct Connection days of yore - Mopar performance cams were either purpleshaft
series or the more aggressive Racer Brown's.
That IS the same Racer Brown you guys are talking about today, right?
It is, but the business was bought by an employee of the original owner. Jim still uses the old grinds however.
 
You guys are worrying me. I installed a Comp Cam 5 yrs/8,000 miles ago, but so far, no problems.
 
I have an old Comp cam in one of my 440's and it looked nothing likes Greg's. So far so good. Myself I've just had problems with their later roller stuff.
 
You guys are worrying me. I installed a Comp Cam 5 yrs/8,000 miles ago, but so far, no problems.
Five years ago, I don't remember seeing a lot of ruckus about quality control over Comp then like
there has been the last few years - so maybe they were still ok then?
 
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