if u have installed a cam lately

[thahemp]

That's true, but what makes switching to another cam successful? In other words, why aren't we talking about them failing too? Is it the lobes? Is it the metal? Is it manufacturing defect?

It would be great to have a definitive answer to these questions. If whatever it is about Comp Cams can be addressed by tweaking the valvetrain, then I'm sure everyone would like to know. It certainly seems like some shops have figured out how to not have them fail. They imply that less aggressive lobes, better matched springs, and larger diameter pushrods are their secrets to success. Or even that Comp tends to not screw up their orders for volume customers?

There are a lot of hypotheses, but not many seem to agree. Tracy, Tick, Pat G, and Spartan all seem to have a slightly different take on the issue.

[dekan513]

im the cases ive seen local. i dnt see them guys building stuff for years and years in ls only cars and nothing going wrong till lately. i had my car down to put a melling pump in it and ls2 chain guide . i should have took the cam out to check it but its been in there for 10k miles so ill leave it alone lol.

[dekan513]

the ls1tech link alot are just blaming comp or the oils for not having zinc in them. from today on im gona start running a zinc additive tho.
i have no cats so no biggie

[thahemp]

Originally Posted by dekan513

the ls1tech link alot are just blaming comp or the oils for not having zinc in them. from today on im gona start running a zinc additive tho.
i have no cats so no biggie

If you read it a little closer, you need the shear performance too. I think that's why a lot of them were recommending the VR-1 over purely zinc-heavy oils. VR-1 is cheap too.

[Bo White]

Don't know why people say zinc kills cats.
I gave my cat one of my one a day zinc supplements and she did just fine........



One more thing I will add to this thread, how many times have springs been installed without checking installed height or spring pressures? Large majority have been installed in car without so much a thought. Sure, people get away with it all the time but so do unprotected sexual experiences but I do have a buddy or two that has a kid now or had to go to the doctor.......
There will always be part failures caused by the part but most part failures can be avoided by just paying attention to detail.

[dekan513]

thats why they said they took zinc out of the oils so i guess thats why ppl say it . just as u said that some may get away with it some may not.

[maxdmax]

Thanks for the pictures and information. The issues on all 3 of my engines looked very similar. On 2 of mine the failures happened at less than 1,500 miles and 2,500 miles and were as bad or worse than those in your pictures. I had a total loss of 2 engines due to lifter damage and the metal particles that went into the bearings and all throughout the engine. In one case one my lifters were actually completely destroyed. Did you have any that failed with very low mileage like mine? My engines were done by a very reputable shop and with their cooperation we sent the engine to another top rated shop to check out completely and rebuild it to assure everything was correctly done. They checkd the install extensively and found that everything was done spot on correctly with the install. I would like to speak to you, I PMed you my contact information. Below is what this can lead to, we actually thought we had a bad lifter until we inspected the other lobes, had more failures and saw more engines that had other failures that did almost the same thing.

Originally Posted by Damian

For those of you wanting to get outside the "Camaro5 realm" for a minute, the first 8 pages of this thread will enlighten you. Comp cams failing isn't an isolated incident...

http://ls1tech.com/forums/showthread...referrerid=183

Pages 1-5 are worth the read for sure. After page ~8-10 it starts getting off topic but pages 1-8 are enlightening.

Attached is a pic of a few Comp cams I've removed within the last 12 months that failed. ALL of these camshafts were installed by other professional shops throughout the southeast. If Comp is right, and Comps vendors are right about what causes them to fail then their logic would suggest there's only 1 oil on the market suitable to run them and not an installer in the entire country that knows how to build an LSX engine. There's some VERY well known camshaft vendors switching over to another manufacturer due to failures. Draw your own conclusions.

[dekan513]

i was reading over the post and tracey was getting to me a lil this morning . so i took a lil time to do some background on him this morning . since he wants to call me out here u go pal.
http://mafia-motorsports.com/forums/...11268&page=118


dont call someone out if u got lots of skeletons in the closet. not very smart. 120 pages of tracey lewis at his best

keep in mind ppl this is his local forum too.

[JEFF75645]

I didn't think it would have lasted this long. Good find Dekan

[dekan513]

lol, i accually thought that he had a good company name . by reading on this forum and how he always talks hisself up. but when u call me out ill call u out lol.

[willhe64]

Originally Posted by thahemp

Yeah, I understand your logic. I guess I'm thinking about it from the perspective that maybe the real culprit is that the valvetrain isn't able to cope with the aggressive lobes. That point made sense to me as another possibility. Launching the lifter could very well cause the marks on those cams. CFD here eventually came to the conclusion that something sheared the pin out of the roller in his lifter. These little details over a few different threads could mesh together to explain things. It is at least plausible.

You guys could very well be right and the hardness of the metal is ruined by grinding, or is insufficient in the first place. I do find it curious that supposedly the cores all come from the same place, and a bunch of shops are reporting no problems. I'm just of the mindset that you don't know until you know. I don't know either!

Originally Posted by Damian

For those of you wanting to get outside the "Camaro5 realm" for a minute, the first 8 pages of this thread will enlighten you. Comp cams failing isn't an isolated incident...

http://ls1tech.com/forums/showthread...referrerid=183

Pages 1-5 are worth the read for sure. After page ~8-10 it starts getting off topic but pages 1-8 are enlightening.

Attached is a pic of a few Comp cams I've removed within the last 12 months that failed. ALL of these camshafts were installed by other professional shops throughout the southeast. If Comp is right, and Comps vendors are right about what causes them to fail then their logic would suggest there's only 1 oil on the market suitable to run them and not an installer in the entire country that knows how to build an LSX engine. There's some VERY well known camshaft vendors switching over to another manufacturer due to failures. Draw your own conclusions.

Looking at those pics tells me the cams are too soft. Not liking the porous look of the metal in the pitted areas either. And the pattern tells me the roller was slowly squeezing a rut into the lobe, until the hard outer layer flaked off on the edges of the path. Geez, wasn't too long ago that roller cams were billet pieces of art. That doesn't even look like forged metal to me.

Valve float from weak springs will hammer the down ramp on the lobe, not the tip.

Too much cam doesn't fly either. We run a lot more aggressive cams than these in full race drag cars and have zero issues.

The poor oil argument fails for me also. These are roller lifters, rolling on a hard surface, where's the friction in that even? I ran a solid lifter cam with massive lift for 8 years, no issues on 15-40w run of the mill oil.

All the evidence we've seen points to a bad batch. Those pics tell me maybe they aren't making them like they used to, trying to save costs on "alternate" materials?

Edit: A camshaft is not made of hard/brittle metal. In one of the final processes the cam is heated to a high temp and coated in carbon and then queched (cooled rapidly). This creates a very hard outer surface. If you don't get this right, the cam will wear out rapidly.

Edit 2: That ls1tech thread backs up my statements.

"I guess it was something during the hardening process on a certain batch of cams sold awhile back.."

"Their cams are fine...just don't get one of the "austempered iron cores". They're treated cast iron, not steel. I've seen several of 'em track with roller lifters."

From my impressions above, about the metal and the rut, those cams are tracking and the metal looks like cast.

[Bo White]

Also one thing to remember is the rocker ratio goes both ways. Lift multiplied one way and spring pressure the other way. 1.7 ratio is alot. If your spring pressures are too high at the valve then its even that much higher at the lobe. Another thing is it looks like the same lobe on those cams. May be something to that.
I will say that the Rockwell hardness needs to be checked on those cams. BBC valve train is similar to the ls in ratio and they do fine. This is one of the smaller reasons for the larger base circle GM designed into the ls platform.

[thahemp]

Originally Posted by willhe64

Looking at those pics tells me the cams are too soft. Not liking the porous look of the metal in the pitted areas either. And the pattern tells me the roller was slowly squeezing a rut into the lobe, until the hard outer layer flaked off on the edges of the path. Geez, wasn't too long ago that roller cams were billet pieces of art. That doesn't even look like forged metal to me.

Valve float from weak springs will hammer the down ramp on the lobe, not the tip.

Too much cam doesn't fly either. We run a lot more aggressive cams than these in full race drag cars and have zero issues.

The poor oil argument fails for me also. These are roller lifters, rolling on a hard surface, where's the friction in that even? I ran a solid lifter cam with massive lift for 8 years, no issues on 15-40w run of the mill oil.

All the evidence we've seen points to a bad batch. Those pics tell me maybe they aren't making them like they used to, trying to save costs on "alternate" materials?

Edit: A camshaft is not made of hard/brittle metal. In one of the final processes the cam is heated to a high temp and coated in carbon and then queched (cooled rapidly). This creates a very hard outer surface. If you don't get this right, the cam will wear out rapidly.

Edit 2: That ls1tech thread backs up my statements.

"I guess it was something during the hardening process on a certain batch of cams sold awhile back.."

"Their cams are fine...just don't get one of the "austempered iron cores". They're treated cast iron, not steel. I've seen several of 'em track with roller lifters."

From my impressions above, about the metal and the rut, those cams are tracking and the metal looks like cast.

Good analysis. Thanks for explaining.

I was actually imagining the lifter launching off an aggressive ramp and being slammed onto the tip by a heavy spring, but it makes more sense that if it is able to leave the lobe... it'll probably clear the top and land on the down side.

So... That's not good news then, should you be spot on.

[willhe64]

I've seen it before, many times. A batch of soft cams. Comp should recall the lot. Sounds like they are quietly replacing them.

Spring pressure is there primarily to make the roller follow the lobe on the down ramp. The profile on the down ramp is there to close the valve as late and as gently as possible. They have no problem following the up ramp all the way to TDC.

I blew an engine from valve float.The valve was slamming into the seat and it popped the head of the valve right off the stem. Punched the valve head through the cylinder head and then filled the cylinder with water, stopping it dead at 6800 rpm. Entire engine gone, all the rods chucked out the block.