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Intake Cam Failures - Materials, Design, or both?

azjl#3

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There is no oil pressure at the sliding cam lobe. I can attest that 100% without question there are problems with many suppliers metal composition with regard to engine internals. Especially during Covid, one of our engine suppliers was having problems with camshafts and bearings not having the proper finish or alloy composition across multiple engine lines as tested in a lab. It is a problem when the source is not properly controlled.
Agreed, aftermarket cam makers, I dabble in engine building 5.0/347 for EB's, were having custom designed cams wipe themselves of lobes in hundreds of miles after build. The makers had no idea until it happened, I mean how, well, crap metal, period
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roaniecowpony

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If I keep this long enough, I'm going 5w40. I'm in Az, the 5 lets it work fine cold, the 40 lets it pur at 120 degrees road temp.

not seeing an oil pressure issue, if it was, you would definitely hear it all the time, everyone would hear it all the time. But, we don't, until it turns into a tick for some people, not all.

I also don't buy some engineer stating to rev it to properly lube the top end. Thats a band aid to a problem not identified and a comment made with no support. 30 psi is plenty to lube everything in that motor, if it wasn't, they would have designed it for 70psi.

The problem is the components wearing. I don't think it's the oil viscosity, although even I am trying 5w30, because if it was mopar would tell us to use 5w30-40. And because not all engines are tapping, it's a segment of some, an obvious imo manufacturing problem, and since it's metal on metal, its a metallurgy 101 failure, not hardened enough, wrong metal, etc.

But, no one will know unless mopar tells us whats behind their curtain, because, they know what it is.
If my suspicions are right, you'd need to instrument the individual passages at each lifter, to detect an oil pressure deviation and it would likely be a subtle delay difference upon start-up from one lifter to the other. The first get Pstar was failing roller rockers. A roller bearing and roller contact require only minimal lubrication, but they kept and keep on failing regardless of brand and revision changes.
 

Matt878

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This is about as statistically relevant as someone who says “I got sunburned every summer, I never got cancer.”

The prevalence of failure of the intake cam on bank 1 is well documented and appears to be at least 15-20x more common than bank 2. This cannot be a coincidence at scale.
hey

I don’t really know where your going with that post lol…

I chimed in because I had the cams and lifters fail at only 13k miles…

just added that thankfully since switching to heavier oil it hasn’t happened since.

bank 1 is not a coincidence…

it reminds me of the LS1 that came stock in my Trans Am. They were notorious for cylinder 7 misfires. This was due to the intake manifold design…cylinder 7 would get air last and developed more heat. It would cause detonation.

there is probably some kind of design flaw within the head just like the LS1 that is causing this issue (on top of 0w20 crap and low end parts)
 

wanted

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Maybe this is an opportunity for the aftermarket to shine with a performance cam options, with maybe a little better performance to boot 😉
 

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bmpcamry09

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Maybe this is an opportunity for the aftermarket to shine with a performance cam options, with maybe a little better performance to boot 😉
In my hopes and dreams that someone who designs cams sees this, I’d like to see a variable cam set up with .32 inches of lift (that’s right in the middle of the low lift and high lift amounts so it won’t break anything) and comes with a set regular roller rocker lifters and dummy plugs with holes for oil flow to eliminate the VVL function but still allow extra oil to get to the rollers 😎

I think we could see 300 HP/300 TQ easily with a setup like that.
 

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Remorseless

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Blacksport

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Use a PAO & Ester based oil (group 4-5), like Redline or Amsoil. Do not a group 3 based oil, which is not true synthetic, despite being labeled as such. Reduce the outlandish coolant temps with the RPM Extreme fan controller and the Mishimoto or Ripp.com 180° thermostat.
 
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bmpcamry09

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What are you saying your fix is?
I disable the high lift function completely and then rewrite the variable cam tables to make the power band smoother and more usable, most 2022 and newer ones allow it to be fully disabled easily with tuning. 2018-2022 is a toss up depending on what software version you have.

My hypothesis is purely speculation. VVL disable might not make them more reliable at all. If my intake cam ever shoots crap I’ll gladly voice my frustration on the forum like everyone else lol.

But I know how much smoother and stronger my Jeep and the dozens I’ve tuned run with that crap disabled and the VVT tuned properly, so hoping it helps on that front.
 

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Same same but different
Jeep Wrangler JL Intake Cam Failures - Materials, Design, or both? {filename}

Dumb movie but funny GIF.

One of these days I'd like to get a hold of one of the failed cams to do some testing on it. I'm curious as to how deep the heat treating penetrates, and how hard the lobes are. I think that there is a good possibility that it's a combination of ill effects that wipe them out with improper treatment of the cam itself, and poor lubrication. If cams are coming from more than one supplier, or if there is variation of the alloys, and heat treating process that would help explain the difference in why some fail faster than others.
 

northernrider

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Well, stating the obvious here, but if it's a manufacturing issue, then that would mean that the bank 1 intake cam is manufactured at a different facility than the bank 2 cam. Does anyone know if this is the case?

I changed my right intake cam, rockers and lifters last summer. 1 lobe on cyl 5 and both for cyl 3 were wiped. I kept the old ones in case Stellantis is ever forced to admit falt in design or materials.

With so many of the PUG on the road, in Challengers, Chargers and Wranglers I'm surprised that the aftermarket never did come out with a performance cam kit.
 
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bmpcamry09

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Well, stating the obvious here, but if it's a manufacturing issue, then that would mean that the bank 1 intake cam is manufactured at a different facility than the bank 2 cam. Does anyone know if this is the case?

I changed my right intake cam, rockers and lifters last summer. 1 lobe on cyl 5 and both for cyl 3 were wiped. I kept the old ones in case Stellantis is ever forced to admit falt in design or materials.

With so many of the PUG on the road, in Challengers, Chargers and Wranglers I'm surprised that the aftermarket never did come out with a performance cam kit.
Good points.

But Chargers and Challengers never got the PUG. They still have the original Pentastar design without VVL and EGR. They manage over 300 HP without the VVL crap the PUGs have.

Pacifica, GC, newer 3.2 Cherokees, Durango, JL, JT, and the last couple years of V6 Rams are all that got the PUG engine.

So both the outside lobes on cylinder 3 were wiped out on your JL? Then the center lobe on cylinder 1? Just want to confirm since most of these I’m seeing just the center high lift low failing. Just curious
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