Cam wiped out, what the hell did I do wrong?!?!?

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Rice Nuker said:
Ive been considering building a metal stand with some gauges to break-in my future engine rather than the in-car break-in.. Put some manifolds with cheap turbo mufflers on it soes I can hear the engine..
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A buddy of mine built one and it works great. We break in all our engines on it.
 
64,
It is entirely possible you have a block with poorly machined lifter bores. This would cause cam failure even if everything was perfect, and is never checked. I don't check for it either, so I wouldn't beat yourself up too much over it if that's the case. This is a real problem with Hughes' cams over the years because they are so aggressive on the rate of lift. It's also why I shy away from max rate of lift cams for street builds. I think in terms of the break in process you did all you could. I don't like the beehives for break in because there's no way to calm them down. If I had to guess, I'd say it was the combination of the spring pressures and possible lifter bore angle issues that did this. Not you or your work. But that's just a guess. The ultimate "fix" would be to have the lifter bores checked and bushed to correct them. Or change cam profiles to something slower and/or get a set of very light springs to break in the new cam. Sorry this happened.
 
I'll probably suck it up and put it on the dyno when I get it back together. I still have to finish tearing it down to see what all I'm going to need. I might even have Brian put it together this time. I don't think I'll go with a Hughes cam this time. Any recommendations on a cam? I'm thinking of the Lunati Voodoo 60404. Need something that will work with 10.1:1 compression, 2500 stall, ported heads, RPM Air Gap.
 
moper said:
64,
It is entirely possible you have a block with poorly machined lifter bores. This would cause cam failure even if everything was perfect, and is never checked. I don't check for it either, so I wouldn't beat yourself up too much over it if that's the case. This is a real problem with Hughes' cams over the years because they are so aggressive on the rate of lift. It's also why I shy away from max rate of lift cams for street builds. I think in terms of the break in process you did all you could. I don't like the beehives for break in because there's no way to calm them down. If I had to guess, I'd say it was the combination of the spring pressures and possible lifter bore angle issues that did this. Not you or your work. But that's just a guess. The ultimate "fix" would be to have the lifter bores checked and bushed to correct them. Or change cam profiles to something slower and/or get a set of very light springs to break in the new cam. Sorry this happened.
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I checked the lifter bores by spraying wd-40 on the lifters and dropping them in. They all dropped in freely, and then I rotated the cam and they went up and down freely and rotated. As added measure, I ran a lifter bore hone through them all before I checked them. I think they were good, but it's possible. I will not go with such an aggressive lift rate on the next cam.
 
I think if you're looking at Lunati the 60404 is good, or the Comp XE284H. I like around 245°-250°@.050 for a street car but you need to figure for the 1.6 rockers.
 
The machined angles you cannot check. It has to be done with a special fixture and they are indexed off the cam centerline. That is why I don't check either. Youchecked for rotation which is the most critical and often skipped. But assuming all else was checked... It's something you didn't/couldn't.
 
The XE284H is another one I'm considering, but I think I remember seeing a Post by Brian (OU812) saying they use that cam in their strokers and make 440 HP. The work on my heads might get me where I want to be (well over 500 HP). According to Hughes, my heads, as built, should support up to 600 HP.
 
64physhy said:
I'll probably suck it up and put it on the dyno when I get it back together. I still have to finish tearing it down to see what all I'm going to need. I might even have Brian put it together this time. I don't think I'll go with a Hughes cam this time. Any recommendations on a cam? I'm thinking of the Lunati Voodoo 60404. Need something that will work with 10.1:1 compression, 2500 stall, ported heads, RPM Air Gap.
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IMO i would drum up the extra money and run a hyd roller, i have heard way too many storys on flattening cam lobes in the past few years, even following all the proper procedures.
 
No offence, but I don’t see you getting anywhere near 600hp or well over 500hp with that cam and those heads. Just my 2 cents….you will need more cam AND heads to put out numbers that are well over 500hp....Also, just because the head “could” support 600hp, doesn’t mean they will...I just don't see it happening.
 
Sorry to hear about your missfortune...

The first things that come to mind is too much spring pressure on start up and second is lifter bore index is out or too loose...
One other thing is that taking a HONE to the lifter bores is a no-no...some 320 on a flapper wheel for a polish is all I use.
The ramp on your cam is really not that aggresive...probably low 140ish@200.
Problems tend to start at 155@200 with flat tappet cams or at least from my experience that's where block issues come into play...ie lifter bores to loose and bore index issues.
See if you can find a broaching tool to check the lifter bores.I've seen the tool fall right out the bottom of the bore on many occasions.
 
How loose/tight should the lifters be in the bore? Is there an accurate way to measure the bores? I had looked for a broaching tool when i was getting ready to assemble it, but couldn't find one. I'll check with one before I put it back together. I hope I don't need a whole new block.
 
64physhy said:
I don't think I'll get near 600, but would like to get 525-550.
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You'll need alot more then what your doing then to even achieve 525, another thing you need to consider is selecting a good converter for the combo that stalls where it needs to, not a 2500 stall, thats damn near stock, wouldn't work too well with the 284H.
 
I dont want to see any bores larger than .906. On a convertor, with a 4" stroke and a moderate cam, I think a convertor of 2500 max will be fine. Street car. Not strip car. These engines pull hard low and you just waste a lot of energy on the street by spinning the convertor to 3500 or more.
 
I've got a friend who rebuilt the 360 in his pickup a little more than two years ago. He had heard of all the stories of cam failures so he meticulously followed the installation recommendations for his Brand C cam including their lube, light springs etc. He was very careful with startup procedures too. (He's a extreme detail sort of guy.) An exhaust lobe went south in less than 200 miles.
He picked up a new Brand L cam and was extremely careful (even more so) on installation and startup. It started wiping two lobes shortly after installation. I went over the Saturday after he discovered the problem to help him pull the engine but when I got there he was fuming. He had just stuck a Mopar Performance cam from a built 340 Duster that he had removed in 1979 into his block. As I stood there questioning his mental stability he was removing lifters from a pipe tobacco can and placing them in the bores (I know, and he knows you never put used lifters back if you don't put 'em on the same lobe but here he is doing it!) while continuing to mutter about proving a point. His high tech assembly lube for each lifter was Lubriplate 105. We continued to bolt it together as I continued to protest the resonability of doing so. Just prior to stabbing the oil pump drive he grabbed the drill and priming rod and spun up some oil pressure and visible oil to the rockers. We finished the final assembly and started it that evening. Well, I've been waiting to hear from him about cam failure for a couple of years now. He drives it daily and it's got over 20,000 miles since he stuck in the used cam with mismatched lifters and it runs great.

If someone can say what he did wrong on the first two cams I would be very interested. He says he has proved his point but he won't clearly say just what that point is!
 
64physhy said:
I don't think I'll get near 600, but would like to get 525-550.
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If you want that kind of power and a 2500 stall converter, I would go roller. You'll need a quick higher lift lobe to get that kind of power without hurting drivability.
 
I guess I'll just settle with whatever I can get out of a cam that will go with my current combo. I have too much into this already, and can't afford a roller lifter set-up or higher stall converter. I could probably do the converter, but am not going to right now. So I guess between the XE284H and Voodoo 60404, the Voodoo is looking like the better choice.
 
The Lunati 60404 will be real mild in a stroker. I have one in my 360 right now and it's not very radical. Just a little lumpy idling. I doubt it'd make much over 450 hp.
 
You will probably need 260ish @ .050 to hit over 500, JMO and FWIW I have never had a cam go flat even when using both springs at break in.
 
grimreaper said:
If someone can say what he did wrong on the first two cams I would be very interested. He says he has proved his point but he won't clearly say just what that point is!
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IMO, he's got the same issues as 64. The modern fast rate cams (meaning the ones designed for the .904 lifter) need everything perfect, or damn close. Lifter bore angles are never, I mean NEVER checked unless the engine is a decent budget deal and getting lifter bushings anyway.The old MP designs don't need things perfect. He did nothing wrong by most standards, but there was still something wrong with the first two setups. It happens.
 
moper said:
I dont want to see any bores larger than .906. On a convertor, with a 4" stroke and a moderate cam, I think a convertor of 2500 max will be fine. Street car. Not strip car. These engines pull hard low and you just waste a lot of energy on the street by spinning the convertor to 3500 or more.
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I agree for what he's doing-app, otherwise....bettr get 300*+ duration cam on a 104-106cl.....and heads that will work there.
 
Moper, I think you hit it on the head. I have never got him to confirm what point he proved but I believe he has convinced himself that the cam companies have developed lobe profiles that perform at faster lift rates at the expense of a propensity for failure if not installed within the exact design specs used to create the designs, which may or may not be within tolerance from block to block. Probably the same issue that 64physhy experienced.
 
Thats a pretty good story.. I like the meticulous installation, its allot easier to pinpoint issues if everything is done by the book or better.. Sounds like your friend experienced modern crappy outsourced metal failure.. What the hells this country coming to? Maybe new flat tappet cams are all shi* since most everything is rollers, potentially rollers dont have to be as hard or something, leaving cam manufacturers to source cheaper or different metal or hardening practices.


grimreaper said:
I've got a friend who rebuilt the 360 in his pickup a little more than two years ago. He had heard of all the stories of cam failures so he meticulously followed the installation recommendations for his Brand C cam including their lube, light springs etc. He was very careful with startup procedures too. (He's a extreme detail sort of guy.) An exhaust lobe went south in less than 200 miles.
He picked up a new Brand L cam and was extremely careful (even more so) on installation and startup. It started wiping two lobes shortly after installation. I went over the Saturday after he discovered the problem to help him pull the engine but when I got there he was fuming. He had just stuck a Mopar Performance cam from a built 340 Duster that he had removed in 1979 into his block. As I stood there questioning his mental stability he was removing lifters from a pipe tobacco can and placing them in the bores (I know, and he knows you never put used lifters back if you don't put 'em on the same lobe but here he is doing it!) while continuing to mutter about proving a point. His high tech assembly lube for each lifter was Lubriplate 105. We continued to bolt it together as I continued to protest the resonability of doing so. Just prior to stabbing the oil pump drive he grabbed the drill and priming rod and spun up some oil pressure and visible oil to the rockers. We finished the final assembly and started it that evening. Well, I've been waiting to hear from him about cam failure for a couple of years now. He drives it daily and it's got over 20,000 miles since he stuck in the used cam with mismatched lifters and it runs great.

If someone can say what he did wrong on the first two cams I would be very interested. He says he has proved his point but he won't clearly say just what that point is!
Click to expand...
 
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