“Wiped Cam Reveal”

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yellow rose said:
What about the FABO member (I'm horrible with names) that had he cam with the taper all ground the same way?

There wasn’t a thing he could do to make that junk work.
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I definitely consider the cam being made wrong as a legitimate reason for failure.
That cam also had way way too much lobe taper(which I haven’t run across myself), and didn’t have any chance of surviving.

Cams failing from inadequate lobe taper...... I see that reasonably often as a reason for a cam not surviving.
Low taper = less lifter rotation...... and if it’s being run with stiff springs, the cam/lifters don’t usually last very long.
 
Had a friend that builds motors on regular basis 2 months ago lost two same exact part number Comp cams on the engine run stand. 2 weeks apart, both bought from Summit. Within 10 min run time.

Put in an old NOS MP cam and lifter kit from 20+ years ago.... all was fine

He talked to his buddies that run a well known shop that machines/cnc/builds/dyno competition class cars and they were not surprised at all. Since all these mergers and buyouts (Holley, Edelbrock...) quality has suffered greatly.
 
So, if it’s a quality issue, what was discovered as the cause of the failure?

In 30 years, of the cams that have gone flat where I was involved with the build........ I can’t think of a single one where we weren’t able to identify what we felt was the cause of the failure........ and after rectifying it....... the next cam survived.
I actually cant think of any motor that we built where the cam had an issue, and we concluded the cam itself was the problem.
 
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Does this count as a cam failure?

Regarding SBC cam failures.

Many of those were caused by the cam tunnel being machined on an angle in GM's engine plant. Talking to a noted engine builder in the 70's ( before aftermarket blocks were available) he would pick and choose what blocks he would use..he rejected 75%.
 
I have been running Hot Cams in my 340 with appropriate springs for 40 years and have swiped one lobe in all that time, that valve also had a broken dampener spring and I believe a piece of the spring may have stopped the lifter rotation. But I can't be sure which happened first the spring breaking or the Lobe swipe . I was also able to catch what looked to me as a bad wear pattern beginning on my current cam early and by swapped out the lifter and have had no further problems. All of my camshafts have either been crane or purple cams. And I think the Mopar performance lifters hydraulics are very good pieces.
 
I wiped one in my 70:challenger 340. My Kid did me a favor and changed oil for me, forgot that It was flat tapped and used regular oil without zinc. 100 miles later the cam was gone along with a bunch of my money to repair.
 
So, so far it’s any number of likely reasons: bad lifters especially from a particular “era” from overseas or elsewhere, improper break-in, the lack of adequate zinc and perhaps other additives in the oils being used. Other possibilities would be cam core quality and how the cams were ground. Then perhaps engine issues relating to lubrication delivery issues, assembly, component selection and possible incompatibility etc. Back in the early/mid 80’s I and a few buddies had various cars and combined we used a Direct Connection 280/474 hyd (440) a Comp Cams solid
marketed as some variable duration via loose/tight lash changes iirc (FE 390) an Isky hyd Super Cam unkn specs (Ford 302) a solid Lunati max wedge cheater (440) even a JC Whitney hyd (Chevy 350) and in the mid 90’s an Erson hyd in a B block 400. Just lubed them with the lube provided, used STP oil treatment, or CRC assembly lube. Some guys used “motor honey” Nobody ever wiped a cam. Lube it up, slide it in. I think there was more concern about nicking cam bearings, and keeping the engine cool during the break-in. We’re talking 17-25 year olds during those days with limited knowledge or experiences yet nobody experienced this wiping crap. :eek:
 
Like 12many I have never wiped out a cam lobein a new or re-cammed build.

My first hot rod project was my buddies '56 Chevy ragtop around 1961. He bought a used tri-power set-up with three 97's and a new Isky cam... couldn't afford new lifters or springs.

The cam install went fine...used lifters and all. The 3x2's deal did not. I was the "expert" on this deal and we could not get the 265 to run...mostly back fire and flames. I'm sure we had the timing off. Looking back I'm surprised we did not wipe out a cam lobe.

When we reinstalled the factory intake/carb we got lucky and hit the timing right away. The car ran great... it was a "3/4 race cam" and did a good job for a year or so until my friend sold the car and it vanished from our school parking lot.

I know many new cam installs are put together with heavier springs than are needed. And some guys just don't have a set of "break-in springs". Or they don't remove the inner springs or they start and stop the engine several times or they don't have the timing right and they crank too much.
 
I've never used a set of break in springs, either. But I also don't run 'hot' solid grinds....if I can't get what I want with a 'medium' solid I'll use a roller.
 
Krooser said:
and they crank too much.
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On my cracked iPhone screen it, at first glance, looked like “and they drank too much” ......that is possible, as beer and working in the garage (looking at a cracked screen or otherwise) go hand in hand:eek:
 
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