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Cam Wiped Lobes Now What?

Something that will make your cam purchasing decision less complicated........

None of the cam grinders make their own cast cores.
They buy them from core manufacturers....... and there are only a couple that supply the entire industry.

Cast cores arrive at the cam grinders “semi-finished”.
Bearing journals are done, gear is cut, heat treat is done.

The cam grinder puts their profile on it, parkerizes it(usually), makes sure it’s straight, qc’s it....... and ships it.

Everyone starts out with the same stuff.
 
The questions I’d have for the OP are.......
-what cam lube was used?
-what oil was used for break in?
-did you check each lifter for proper rotation?
 
I didn't realize the cores were all that similar. But I don't have issues with any of them anyway.
IMO - every camshaft has a corresponding matching spring from the manufacturer. My impression is the 924-16s would have sufficed, but regardless of what the OP felt, the inner springs are supposed to be out for break in. And - that should have happened after the rotation was verified during assembly. So you did yourself in IMO.
IN regard to "what to do now" - I only have one approach when dealing with a cam failure: tear it down to bare block, clean it well (brushing out all the oil galleys), and replace all the bearings, rings, and potentially pistons. Iron will imbed in the pistons and that will trash the bores over time too. So that's what Id recommend.
Oh - and verify lifter rotation, and follow the directions on assembly and break in TO THE LETTER. They're written by people much smarter than us.
 
As hobbyist it's easier to blame the camshaft manufacture than the installer (typically ourselves).

On this last camshaft install (fresh engine), I went with Comp Cams 10W-30 break-in oil. At $7/qt. it's not necessarily inexpensive, but it's a lot more expensive if the camshaft wipes a lobe within the first thirty minutes of run time. What I've done in the past is run it the full 30-minutes, that has never seemed to work out well for me. Now, it's 15-minutes run time, change oil & filter, run it again for 15 or 20-minutes. Wix standard filter. Move to the Wix Racing filter post break-in. Don't let it idle, get it out on the street with a load for a few hundred miles.

Assembly lube will pack into the oil filter very quickly, it just seems like good practice to replace the filter before it causes oil pressure fluctuations.

Oil related post by Warren Johnson in National Dragster, good read for those wanting to understand a bit more on the subject;
It's important to recognize that viscosity is only a measure of an oil's flow characteristics at a fixed temperature. It says nothing about an oil's shear strength or its load-carrying capacity. Molasses, for example, is a high-viscosity liquid, but it is not a suitable engine lubricant.
In fact, oil is a very complex mixture of ingredients. Beginning with a base of either mineral oil (distillates of petroleum or coal) or synthetic oil (olefin polymers, esters, ethers, silicones, fluorinated hydrocarbons, and Lord knows what else), a refiner augments the oil chemistry with additives. These additives may include viscosity index improvers, oxidation and corrosion inhibitors, detergent and dispersant additives, friction modifiers, anti-foaming agents, and extreme pressure additives. A lot of technology goes into a can of oil!
One of the advantages of synthetic oils over conventional mineral-based oil is that most synthetics' load-carrying capacity is roughly twice the capacity of conventional oil. This load carrying is what prevents metal-to-metal contact between moving parts, not the viscosity of the oil. In addition, synthetic oils do not seem to be as sensitive to temperature-induced viscosity changes as mineral-based oils.
It is crucial to understand the relationship between oil viscosity and oil temperature. As the temperature of the oil increases, its viscosity decreases. It's like heating maple syrup in a microwave (I'm talking about real maple syrup, not that maple-flavored goo that's sold in squeeze bottles!). At cold temperatures, the syrup flows like gear oil; zap it in the microwave for a few seconds, and it pours like water. Oil works the same way, which is why you need to specify the temperature in any discussion about an oil's viscosity.
Multigrade oils, such as 10W-30, include viscosity index modifiers that allow the oil to act like a low-viscosity oil at low temperatures and a high-viscosity oil at elevated temperatures. SAE oil grades followed by a "W" (as in "Winter") refer to oils used in cold climates, and their viscosity is determined at zero degrees F (which was a pretty nice spring day where I formerly lived in Minnesota). SAE grades without a "W" are based on the oil viscosity at 210 degrees F. In a multigrade oil rating, 10W-40, for example, the first number indicates viscosity at zero degrees F and the second number refers to the viscosity at 210 degrees F.
Relying strictly on SAE numbers to judge an oil's suitability for racing can be misleading. Obviously, drag racers do not run their engines when the temperature is below freezing, and we never see oil temperatures as high as 210 degrees, even on the hottest summer days. The oil's characteristics in the temperature range in which it actually operates is what's important.
Engine oils typically exhibit their best lubricating qualities at temperatures between 200 and 210 degrees F. If you dyno test an engine with its oil at 150 degrees and then repeat the test with the oil at 200 degrees, you can expect a 1-percent increase in power at the higher temperature. Unfortunately, we don't have the ability to get the oil temperature to the 200-degree range in a Pro Stock engine. Even after preheating the oil and warming up the engine before a run, we seldom see oil temperatures higher than 150 degrees. Therefore, we use low-viscosity oil that emulates the flow characteristics of a heavier oil operating at higher temperature. That is the primary reason why we see a measurable power increase with low-viscosity oil.
Reduced windage losses also contribute to the power increase produced by low-viscosity oil. With a lighter oil, the rotating assembly (crankshaft and connecting rods) encounters less resistance as it churns its way through the "slurry" of air and oil in the crankcase. Imagine stirring a pail of mud with a paddle; that's essentially what the rotating assembly has to do when the crankcase is filled with a dense mist of conventional heavyweight racing oil.
An oil's coefficient of friction also plays a significant role in engine performance. Friction is a concern at high-temperature areas such as the top of the piston-ring travel. The top of a cylinder bore is a very inhospitable place in a high-speed engine. In addition to hellish temperature, there is a lack of lubrication because the oil rings, the second scraper rings, and all of the measures taken to control internal oil flow conspire to minimize the oil on the cylinder walls. Thus, the oil's load-carrying capacity and its ability to adhere to the metal surfaces affect both piston-ring life and the quality of the cylinder seal.
The friction between the rings and the cylinder walls accounts for a large percentage of the parasitic losses in an engine. Any steps you take to improve the sliding motion of the rings by using oils that adhere better to the cylinder walls and have better lubricating qualities and higher load-carrying capacities will tend to increase power and reduce wear.
Similarly, reducing bearing friction by using oil with a lower coefficient of friction can also increase power, though the potential gains in this area are not as great as the improvements that can be achieved by reducing ring friction.
There is a myth among racers that you cannot break in an engine with synthetic oil. At our shop, we start and break in a new engine using the same synthetic oil that we use at the racetrack. Modern piston rings are lapped during the manufacturing process with crowned faces, and honing techniques have improved dramatically over the years. Thanks to these advances, the mating of the ring face to the cylinder wall is no longer an issue, regardless of the type of oil that is used.
That is a long answer to a short question. Oil is obviously a very complex subject, and I didn't want to let this one just slide by.
 
Quite a few years ago I was involved with a team that was stepping up into a more serious oval track class than what they had been running.
They bought a used turn key car, but the motor rules were slightly different than what was allowed up here.
The primary discrepancy was the cam.
It had a roller and the local rules were flat tappet.

This was a w2 headed 358 in an X block with a dry sump.

The motor got freshened, swapped out the cam, went through the heads, etc...... brought it to the dyno.

Eats a cam lobe pretty much right off the bat. Chopped right down.
14 lobes look perfect, one is “eh”, one is toast.

Had the cam tested for hardness, just out of curiosity really....... it was right at R50 on the c scale everywhere they tested it....... even right on the nose of the chopped lobe.

After some further investigation, it was discovered there was no rotation on the lifter bore where the chopped lobe was, and extremely poor rotation on the bore where the iffy lobe was.

Tried a cam made with an extra thou of lobe taper...... still zero rotation from the one bore.

The block had been bushed, thought, okay..... a bushing is worn.
No one around here had the tooling for a 59* sb mopar, so the block gets sent back to where it was done originally.

Block comes back, all new bushings...... still no rotation out of the one bore!!!

After a few phone conversations, and then bringing the block to a machine shop(non-engine type), he did some measuring...... then pulled that lifter bushing..... and determined that the bore had been reamed slightly off, which is why there was no rotation.

Anyway....... long story to emphasize the importance of proper lifter rotation.
 
As for the “what now”, or rather..... what to do for the next cam break in.....

I use Driven “BR” oil. It’s 15/50.
I always use the grey/black moly paste for cam lube on flat tappet cams.
On the lobes and lifter faces.

Ordinarily I would have left the inner springs in on 924 springs, but since that didn’t work out last time, I’d pull the inners for the next attemp.

Positively verify you have decent lifter rotation during assembly.
If you don’t, you’ll be repeating this excercize again.
 
moobster said:
A quick hone wouldn't hurt. You gotta pull it apart anyways, to clean the trash out off all the oil galleries. Pull the cam plug from the back of the motor too, alot of grindings stay there.
I'm not a fan of Lunati, never was. A friend of mine bought one for his Pontiac engine and the cam journals were .002" over sized. Wouldn't go in the motor.
If they can't get their machining right, what makes you think they can get their case hardening right.
Click to expand...
It was a Lunati I found wiped out in the car I purchased. Who knows. I decided on Crower and they have appeared top notch from initial contact to installed product.
 
PRHeads said:
As for the “what now”, or rather..... what to do for the next cam break in.....

I use Driven “BR” oil. It’s 15/50.
I always use the grey/black moly paste for cam lube on flat tappet cams.
On the lobes and lifter faces.

Ordinarily I would have left the inner springs in on 924 springs, but since that didn’t work out last time, I’d pull the inners for the next attemp.

Positively verify you have decent lifter rotation during assembly.
If you don’t, you’ll be repeating this excercize again.
Click to expand...
Ok so how are you determining proper lifter turn? Are you just turning by hand and watching each one?? What is the proper way? Like I said I had 2 successful cams before this one or I might question the bores
 
Bicylindrico said:
It was a Lunati I found wiped out in the car I purchased. Who knows. I decided on Crower and they have appeared top notch from initial contact to installed product.
Click to expand...
I broke both of my Racer Brown cams in the the way Jim described and had zero problems! He did not have a big long drawn out procedure like others have described just says “keep those R’s up above 2000 for 20 minutes” No problems
 
moper said:
I didn't realize the cores were all that similar. But I don't have issues with any of them anyway.
IMO - every camshaft has a corresponding matching spring from the manufacturer. My impression is the 924-16s would have sufficed, but regardless of what the OP felt, the inner springs are supposed to be out for break in. And - that should have happened after the rotation was verified during assembly. So you did yourself in IMO.
IN regard to "what to do now" - I only have one approach when dealing with a cam failure: tear it down to bare block, clean it well (brushing out all the oil galleys), and replace all the bearings, rings, and potentially pistons. Iron will imbed in the pistons and that will trash the bores over time too. So that's what Id recommend.
Oh - and verify lifter rotation, and follow the directions on assembly and break in TO THE LETTER. They're written by people much smarter than us.
Click to expand...
How is everyone verifying lifter rotation. I know how it rotates just didn’t know to verify it. Makes sense though
 
Lifters don't stand still when the lobe lifts it. There's taper ground into the lobe, and a crown on the lifter so the lifter will turn as the lobe moves it. The way I verify it is to install the cam and timing set, spray the lifter bores and lifters with WD40, and slide them in the bores. No other materials on the cam or lifter face when this is done. I mark the block and the lifter with a sharpie, and then turn the engine over by hand. The mark on the lifter moves (not a ton, but all you need is 4-7* per lift cycle) and the block doesn't. If the lifters all rotate with nothing aside from the weight of the lifter, it will be good. Most times there's one or two that don't, and some shuffling around usually fixes that. Like Duane I use a combination of synthetic paste and a little assembly lube to thin it slightly - makes it easier to brush on - and only on the lobes and the lifter faces. I brush it on after the cam is installed and degreed, and lifter preload and pushrod length are checked and known. Basically it's the last thing I do before the intake goes on. IMO liquid break in additives are useless. The mating surfaces need a paste that stays put for a few rotations of the engine.
The lifter bores are as highly aligned as the factory machined decks and bores (choking while saying that). So you have to make sure the **** will work. In some cases they simply won't because of wear, or misalignment, or a problem cam or lifter. But if you look, you'll find out there's an issue, and that means you look deeper.
 
Sweet5ltr said:
As hobbyist it's easier to blame the camshaft manufacture than the installer (typically ourselves).

On this last camshaft install (fresh engine), I went with Comp Cams 10W-30 break-in oil. At $7/qt. it's not necessarily inexpensive, but it's a lot more expensive if the camshaft wipes a lobe within the first thirty minutes of run time. What I've done in the past is run it the full 30-minutes, that has never seemed to work out well for me. Now, it's 15-minutes run time, change oil & filter, run it again for 15 or 20-minutes. Wix standard filter. Move to the Wix Racing filter post break-in. Don't let it idle, get it out on the street with a load for a few hundred miles.

Assembly lube will pack into the oil filter very quickly, it just seems like good practice to replace the filter before it causes oil pressure fluctuations.

Oil related post by Warren Johnson in National Dragster, good read for those wanting to understand a bit more on the subject;
It's important to recognize that viscosity is only a measure of an oil's flow characteristics at a fixed temperature. It says nothing about an oil's shear strength or its load-carrying capacity. Molasses, for example, is a high-viscosity liquid, but it is not a suitable engine lubricant.
In fact, oil is a very complex mixture of ingredients. Beginning with a base of either mineral oil (distillates of petroleum or coal) or synthetic oil (olefin polymers, esters, ethers, silicones, fluorinated hydrocarbons, and Lord knows what else), a refiner augments the oil chemistry with additives. These additives may include viscosity index improvers, oxidation and corrosion inhibitors, detergent and dispersant additives, friction modifiers, anti-foaming agents, and extreme pressure additives. A lot of technology goes into a can of oil!
One of the advantages of synthetic oils over conventional mineral-based oil is that most synthetics' load-carrying capacity is roughly twice the capacity of conventional oil. This load carrying is what prevents metal-to-metal contact between moving parts, not the viscosity of the oil. In addition, synthetic oils do not seem to be as sensitive to temperature-induced viscosity changes as mineral-based oils.
It is crucial to understand the relationship between oil viscosity and oil temperature. As the temperature of the oil increases, its viscosity decreases. It's like heating maple syrup in a microwave (I'm talking about real maple syrup, not that maple-flavored goo that's sold in squeeze bottles!). At cold temperatures, the syrup flows like gear oil; zap it in the microwave for a few seconds, and it pours like water. Oil works the same way, which is why you need to specify the temperature in any discussion about an oil's viscosity.
Multigrade oils, such as 10W-30, include viscosity index modifiers that allow the oil to act like a low-viscosity oil at low temperatures and a high-viscosity oil at elevated temperatures. SAE oil grades followed by a "W" (as in "Winter") refer to oils used in cold climates, and their viscosity is determined at zero degrees F (which was a pretty nice spring day where I formerly lived in Minnesota). SAE grades without a "W" are based on the oil viscosity at 210 degrees F. In a multigrade oil rating, 10W-40, for example, the first number indicates viscosity at zero degrees F and the second number refers to the viscosity at 210 degrees F.
Relying strictly on SAE numbers to judge an oil's suitability for racing can be misleading. Obviously, drag racers do not run their engines when the temperature is below freezing, and we never see oil temperatures as high as 210 degrees, even on the hottest summer days. The oil's characteristics in the temperature range in which it actually operates is what's important.
Engine oils typically exhibit their best lubricating qualities at temperatures between 200 and 210 degrees F. If you dyno test an engine with its oil at 150 degrees and then repeat the test with the oil at 200 degrees, you can expect a 1-percent increase in power at the higher temperature. Unfortunately, we don't have the ability to get the oil temperature to the 200-degree range in a Pro Stock engine. Even after preheating the oil and warming up the engine before a run, we seldom see oil temperatures higher than 150 degrees. Therefore, we use low-viscosity oil that emulates the flow characteristics of a heavier oil operating at higher temperature. That is the primary reason why we see a measurable power increase with low-viscosity oil.
Reduced windage losses also contribute to the power increase produced by low-viscosity oil. With a lighter oil, the rotating assembly (crankshaft and connecting rods) encounters less resistance as it churns its way through the "slurry" of air and oil in the crankcase. Imagine stirring a pail of mud with a paddle; that's essentially what the rotating assembly has to do when the crankcase is filled with a dense mist of conventional heavyweight racing oil.
An oil's coefficient of friction also plays a significant role in engine performance. Friction is a concern at high-temperature areas such as the top of the piston-ring travel. The top of a cylinder bore is a very inhospitable place in a high-speed engine. In addition to hellish temperature, there is a lack of lubrication because the oil rings, the second scraper rings, and all of the measures taken to control internal oil flow conspire to minimize the oil on the cylinder walls. Thus, the oil's load-carrying capacity and its ability to adhere to the metal surfaces affect both piston-ring life and the quality of the cylinder seal.
The friction between the rings and the cylinder walls accounts for a large percentage of the parasitic losses in an engine. Any steps you take to improve the sliding motion of the rings by using oils that adhere better to the cylinder walls and have better lubricating qualities and higher load-carrying capacities will tend to increase power and reduce wear.
Similarly, reducing bearing friction by using oil with a lower coefficient of friction can also increase power, though the potential gains in this area are not as great as the improvements that can be achieved by reducing ring friction.
There is a myth among racers that you cannot break in an engine with synthetic oil. At our shop, we start and break in a new engine using the same synthetic oil that we use at the racetrack. Modern piston rings are lapped during the manufacturing process with crowned faces, and honing techniques have improved dramatically over the years. Thanks to these advances, the mating of the ring face to the cylinder wall is no longer an issue, regardless of the type of oil that is used.
That is a long answer to a short question. Oil is obviously a very complex subject, and I didn't want to let this one just slide by.
Click to expand...
Ok so a couple questions here. Are you saying your using a whole case of break in oil;2 oil changes? Are you first using break in oil, then drain and conventional oil with racing filter? Can you be more specific?
Also when you take this out and load it are you just Sunday driving, highway cruise speed, or hammer it?
 
moper said:
Lifters don't stand still when the lobe lifts it. There's taper ground into the lobe, and a crown on the lifter so the lifter will turn as the lobe moves it. The way I verify it is to install the cam and timing set, spray the lifter bores and lifters with WD40, and slide them in the bores. No other materials on the cam or lifter face when this is done. I mark the block and the lifter with a sharpie, and then turn the engine over by hand. The mark on the lifter moves (not a ton, but all you need is 4-7* per lift cycle) and the block doesn't. If the lifters all rotate with nothing aside from the weight of the lifter, it will be good. Most times there's one or two that don't, and some shuffling around usually fixes that. Like Duane I use a combination of synthetic paste and a little assembly lube to thin it slightly - makes it easier to brush on - and only on the lobes and the lifter faces. I brush it on after the cam is installed and degreed, and lifter preload and pushrod length are checked and known. Basically it's the last thing I do before the intake goes on. IMO liquid break in additives are useless. The mating surfaces need a paste that stays put for a few rotations of the engine.
The lifter bores are as highly aligned as the factory machined decks and bores (choking while saying that). So you have to make sure the **** will work. In some cases they simply won't because of wear, or misalignment, or a problem cam or lifter. But if you look, you'll find out there's an issue, and that means you look deeper.
Click to expand...
Ok awesome info! Synthetic paste?? What brand? Never heard of it. I guess my biggest question now is how can I insure the Piston skirts were not damaged? That’s my biggest worry $700
 
Roadrunner40 said:
Ok so a couple questions here. Are you saying your using a whole case of break in oil;2 oil changes? Are you first using break in oil, then drain and conventional oil with racing filter? Can you be more specific?
Also when you take this out and load it are you just Sunday driving, highway cruise speed, or hammer it?
Click to expand...

15-minutes, drain the oil, new filter. Reuse break-in oil, run for 15 to 20 more minutes. Drain oil, new filter, new synthetic oil. Highway cruising at variable speed RPM, minimal idling.
 
Sweet5ltr said:
15-minutes, drain the oil, new filter. Reuse break-in oil, run for 15 to 20 more minutes. Drain oil, new filter, new synthetic oil. Highway cruising at variable speed RPM, minimal idling.
Click to expand...
Wow so on average that is 18-21 qts of oil that’s a $150-$200 in oil and filters. Do you change it again after the load driving? No offense but is this a little overboard?
Did they do this at the factory? I understand the quality is in question but still. Is this normal practice? Wow that’s a lot when do you get to enjoy it? Please don’t take any offense I know I’m the one with the wiped cam lol
 
moper said:
I didn't realize the cores were all that similar. But I don't have issues with any of them anyway.
IMO - every camshaft has a corresponding matching spring from the manufacturer. My impression is the 924-16s would have sufficed, but regardless of what the OP felt, the inner springs are supposed to be out for break in. And - that should have happened after the rotation was verified during assembly. So you did yourself in IMO.
IN regard to "what to do now" - I only have one approach when dealing with a cam failure: tear it down to bare block, clean it well (brushing out all the oil galleys), and replace all the bearings, rings, and potentially pistons. Iron will imbed in the pistons and that will trash the bores over time too. So that's what Id recommend.
Oh - and verify lifter rotation, and follow the directions on assembly and break in TO THE LETTER. They're written by people much smarter than us.
Click to expand...
What can I do to ensure Pistons are ok?? Don’t want to replace them too much money. Planning on bearings and rings obviously. But boring and new Pistons I’m hoping are fine
 
Roadrunner40 said:
Wow so on average that is 18-21 qts of oil that’s a $150-$200 in oil and filters. Do you change it again after the load driving? No offense but is this a little overboard?
Did they do this at the factory? I understand the quality is in question but still. Is this normal practice? Wow that’s a lot when do you get to enjoy it? Please don’t take any offense I know I’m the one with the wiped cam lol
Click to expand...

Well, I’m reusing the same 10w-30 Comp Cams oil for the initial break in duration, just changing filters after 15-minutes (use standard wix filter during this cycle). Let it cool down, drain the oil, install a another new filter, and pouring used oil back into the engine, varying engine speed from 2000-2500 RPM for another 20 or so minutes.

Then,
New oil and filter (Mobil 1 15w-50 & Wix Racing) after and drive the car for a few hundred more miles, varying load and rpm.
 
Sweet5ltr said:
Well, I’m reusing the same 10w-30 Comp Cams oil for the initial break in duration, just changing filters after 15-minutes (use standard wix filter during this cycle). So draining the oil and pouring it back into the car, varying engine speed from 2000-2500 RPM for another 20 or so minutes.

Then,
New oil and filter (Mobil 1 15w-50 & Wix Racing) after and drive the car for a few hundred more miles, varying load and rpm.
Click to expand...
Ok so why do you drain oil then pour it back in? Couldn’t you just change filter?
 
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