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Old 02-07-2025, 03:52 PM   #1
realsteelGM
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Question Comp Cams

I ran a mellings MTC 1 Camshaft in a complete rebuilt 1958-283. Lasted 14 years until one of the lobes wore down. Replaced this MTC camshaft with a Comp cam 12-230-2. Why are the lobes almost an 1/8 of an inch thinner compared to the beefy MTC camshaft? These are both flat tappet cams.
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Old 02-07-2025, 09:21 PM   #2
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Re: Comp Cams

.

I've noticed many food items at the grocery contain less product for the same price these days. What was once a 22 oz beer is now like 18.2 oz but same price (I'm looking at you Deep Ellum Brewery).

This is called shrinkflation.

What you are seeing is likely something similar! LobeShrinkFlation perhaps?

-Kevin
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Old 02-08-2025, 12:58 AM   #3
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Re: Comp Cams

I can't answer that BUT,.....I can tell you I used a Comp Cam one time.......and it lost about 6 lobes all at once on a fresh sbc build. This was at about 5000 miles, well after break in. Comp didn't care at all and did NOT stand behind their product. Lucky for me the sales rep at the well known retailer was very helpful and asked me to send him the cam. After receiving the COMP CAM he called me back and told me it was the WORST cam core they had ever seen and will be displayed on their "wall of shame".....several air bubbles plainly visible in the worn off lobes and questionable metalurgy. They let me have a new cam and lifters of my choice (NOT COMP) and sent me a new gasket set. That was it for me......NEVER AGAIN will I ever buy anything with Comp Cams name on it.
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Old 02-08-2025, 08:07 AM   #4
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Lightbulb Re: Comp Cams

Three things to keep in mind in today's world-

1. Do not use any recently produced flat tappet cams. The main issues are the metallurgy and the machining of the lifters, not the lack of zinc in the oil. Run NOS parts or roller cams.

2. Comp cams are mediocre at best. I would be looking at other manufacturers. Older stock is better regardless.

3. While the lack of zinc can cause issues, it isn't the only thing contributing to these issues. Still run a high quality oil with zinc in these older engines
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Old 02-08-2025, 01:23 PM   #5
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Re: Comp Cams

Quote:
Originally Posted by weq92f View Post
.

I've noticed many food items at the grocery contain less product for the same price these days. What was once a 22 oz beer is now like 18.2 oz but same price (I'm looking at you Deep Ellum Brewery).

This is called shrinkflation.

What you are seeing is likely something similar! LobeShrinkFlation perhaps?

-Kevin
I'm quite well versed in poor quality products, just looking for a good alternative. As I live Canada, we get jacked by our government and pay twice the price of all American automotive parts coming into Canada.
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Old 02-08-2025, 01:29 PM   #6
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Re: Comp Cams

Anybody in this thread should watch this, like Jesus, you don't have to believe it. Some people do, some don't. It is interesting though.
https://www.youtube.com/watch?v=WzYHae7yXiA
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Old 02-08-2025, 01:31 PM   #7
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Re: Comp Cams

I have always had good luck with Crane Cams.
I don't know how there Quality is nowadays.

Comp cams has never been great IMHO.

I have seen some people have bad luck with their products.
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Old 02-08-2025, 02:57 PM   #8
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Re: Comp Cams

Quote:
Originally Posted by Myself View Post
I can't answer that BUT,.....I can tell you I used a Comp Cam one time.......and it lost about 6 lobes all at once on a fresh sbc build. This was at about 5000 miles, well after break in. Comp didn't care at all and did NOT stand behind their product. Lucky for me the sales rep at the well known retailer was very helpful and asked me to send him the cam. After receiving the COMP CAM he called me back and told me it was the WORST cam core they had ever seen and will be displayed on their "wall of shame".....several air bubbles plainly visible in the worn off lobes and questionable metalurgy. They let me have a new cam and lifters of my choice (NOT COMP) and sent me a new gasket set. That was it for me......NEVER AGAIN will I ever buy anything with Comp Cams name on it.
How long ago did you install the the comp cam that cratered at break in? At this point I've got about 3 grand into the rebuild and need a good cam to put into this, what would you recommend?
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Old 02-08-2025, 03:01 PM   #9
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Re: Comp Cams

I’ve used hundreds of CompCams with never an issue. Of course, any company can have a bad part, and for flat-tappet cams having the valves adjusted correctly, the right assembly lube, the right oil, and the right break-in technique is crucial.

Lobe width outside of the contact point of the lifter doesn’t do anything but increase rotating mass; it doesn’t make it more “beefy”.
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Old 02-08-2025, 03:05 PM   #10
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Re: Comp Cams

Quote:
Originally Posted by 1970cstblazer View Post
Three things to keep in mind in today's world-

1. Do not use any recently produced flat tappet cams. The main issues are the metallurgy and the machining of the lifters, not the lack of zinc in the oil. Run NOS parts or roller cams.

2. Comp cams are mediocre at best. I would be looking at other manufacturers. Older stock is better regardless.

3. While the lack of zinc can cause issues, it isn't the only thing contributing to these issues. Still run a high quality oil with zinc in these older engines
Where would I find older stock cams? Are there any name brands you can think of for this application? Here in Canada a set of roller cam and lifters runs about $2000 not including springs and timing gears.
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Old 02-08-2025, 03:10 PM   #11
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Re: Comp Cams

Quote:
Originally Posted by Getter-Done View Post
I have always had good luck with Crane Cams.
I don't know how there Quality is nowadays.

Comp cams has never been great IMHO.

I have seen some people have bad luck with their products.
What cam do you have in your rig?
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Old 02-08-2025, 03:24 PM   #12
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Re: Comp Cams

Quote:
Originally Posted by Willshook View Post
I’ve used hundreds of CompCams with never an issue. Of course, any company can have a bad part, and for flat-tappet cams having the valves adjusted correctly, the right assembly lube, the right oil, and the right break-in technique is crucial.

Lobe width outside of the contact point of the lifter doesn’t do anything but increase rotating mass; it doesn’t make it more “beefy”.
At this point with 3 grand into the build, I need to know what is going to work. Should I put the comp cam back in the block that is broke in already with only 1500 miles on it? Or do I put a new one in? Or a full roller cam set-up?
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Old 02-08-2025, 03:49 PM   #13
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Re: Comp Cams

Quote:
Originally Posted by realsteelGM View Post
At this point with 3 grand into the build, I need to know what is going to work. Should I put the comp cam back in the block that is broke in already with only 1500 miles on it? Or do I put a new one in? Or a full roller cam set-up?
I'm not sure what you're asking - I'd have no hesitation to put the CompCams back in, with all the prep I noted before. While there's certainly garbage no-name parts out there that are junk, I don't buy anything from the video for anything name brand. Certainly nothing wrong with checking everything, but...

Without knowing more about the engine, I can't advise on a roller cam. CR? heads? Engine RPM range?

In general, the cam you noted is very mild, so a roller in the same lift range isn't really going to make any real difference in performance and retrofit rollers ain't cheap. Keep in mind you also need to positively retain the cam in a retrofit roller, so it's not just a cam swap.

Have you been running an oil with at least 1000 PPM ZDDP?

Last edited by Willshook; 02-08-2025 at 03:58 PM.
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Old 02-08-2025, 03:49 PM   #14
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Re: Comp Cams

Quote:
Originally Posted by jumpsoffrock View Post
Anybody in this thread should watch this, like Jesus, you don't have to believe it. Some people do, some don't. It is interesting though.
https://www.youtube.com/watch?v=WzYHae7yXiA
Watched this, good knowledge! Cam angle will be first thing I'll be checking on a new cam.
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Old 02-08-2025, 03:53 PM   #15
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Re: Comp Cams

When you replaced the cam that went flat, what else did you do to the motor?
Did you tear it down completely and hot tank it?
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Old 02-08-2025, 06:10 PM   #16
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Re: Comp Cams

Seeing this post reminds me of my situation. A couple of years ago (?) started seeing a lot of chatter about flat tappet cam failures. Whatever the actual reason, it prompted me to remove the flat tappet cam kit I had installed on my freshly built, but not yet run, SBC. I went with a Howard's Cam retro roller kit. I figured the extra cost on the front end would offset the potential damage and $ of a complete tear down due to a cam/lifter failure.
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Old 02-08-2025, 10:27 PM   #17
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Re: Comp Cams

Quote:
Originally Posted by realsteelGM View Post
What cam do you have in your rig?
Comp cam 12-230-12
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Old 02-08-2025, 10:35 PM   #18
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Re: Comp Cams

Quote:
Originally Posted by geezer#99 View Post
When you replaced the cam that went flat, what else did you do to the motor?
Did you tear it down completely and hot tank it?
Yes all of the above. All new internals including another forged steel crank. When the cam went, it released shrapnel into the oil and all through the bearings. Scored the crank, and spun a rod bearing. I think this is oil related, I wasn't aware of the oil composition changing and zinc additives.
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Old 02-08-2025, 10:41 PM   #19
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Re: Comp Cams

Quote:
Originally Posted by Getter-Done View Post
I have always had good luck with Crane Cams.
I don't know how there Quality is nowadays.

Comp cams has never been great IMHO.

I have seen some people have bad luck with their products.
I remember crane cam decals as a young boy while making model cars. They have certainly been around. I am going to look into them, see if they have old stock cams tucked away.
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Old 02-08-2025, 10:50 PM   #20
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Re: Comp Cams

Quote:
Originally Posted by HalfBrit View Post
Seeing this post reminds me of my situation. A couple of years ago (?) started seeing a lot of chatter about flat tappet cam failures. Whatever the actual reason, it prompted me to remove the flat tappet cam kit I had installed on my freshly built, but not yet run, SBC. I went with a Howard's Cam retro roller kit. I figured the extra cost on the front end would offset the potential damage and $ of a complete tear down due to a cam/lifter failure.
Is your motor still running with the cam set-up? I priced one here in Yukon, Canada $2100 plus springs and timing assembly.
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Last edited by realsteelGM; 02-08-2025 at 10:56 PM. Reason: grammar
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Old 02-09-2025, 12:57 AM   #21
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Re: Comp Cams

The Jeep forum I'm on has a lot of folks who had been happy users of Comp cams for years, but have had problems wiping them on break-in in recent years
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Old 02-09-2025, 01:18 AM   #22
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Re: Comp Cams

After my boss had a comp cam go flat in a 66 Shelby with less than 50 miles I found this while looking at cams. The new cam from Holman and moody was sent here and broken in. Way less stress on startup without the worry of the break in on the cam. Worth the money in my opinion.
https://www.camresearchcorp.com/cam-...haft-break-in/
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Old 02-09-2025, 05:27 AM   #23
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Re: Comp Cams

Never mind
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Old 02-09-2025, 05:28 AM   #24
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Re: Comp Cams

Never mind
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Old 02-09-2025, 09:59 AM   #25
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Re: Comp Cams

Before you install the next cam, you probably want to watch this video. They actually take a flat tappet lifter on a grinder after the blue it up and you can see the problems. He shows they were Crower lifters.

At this point, I would spend the dollars and put a roller in it.

https://www.youtube.com/watch?v=MbRjAMhCEJk
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