I did a bad thing
Thread Starter
Drifting
Joined: Jun 2000
Posts: 1,476
Likes: 1
From: Mt Juliet TN
I did a bad thing
I guess I didn't adjust one of my valves right because I wiped out one of the lobes on my cam. Cylinder 7 exhaust. On the bright side I did get the other 15 right 
The cam lobe itself is almost flat thats how I figured it out I noticed it wasn't lifting as high as the other rockers
So its back to the drawing board. I decided to try a crane cam (278) this time. I don't think this was a problem with the comp cam I was using this being my first cam swap I'm sure I screwed it up but I had such a hard time tuning the carb with that lumpy idle I went to a crane with a 114 lobe center. Hopefully that will help. I've almost got the engine back apart but its slow going It is hard to get psyched when you just got through doing it. Actually the cam swap isn't that bad except for that stupid fan shroud
The cam lobe itself is almost flat thats how I figured it out I noticed it wasn't lifting as high as the other rockers So its back to the drawing board. I decided to try a crane cam (278) this time. I don't think this was a problem with the comp cam I was using this being my first cam swap I'm sure I screwed it up but I had such a hard time tuning the carb with that lumpy idle I went to a crane with a 114 lobe center. Hopefully that will help. I've almost got the engine back apart but its slow going It is hard to get psyched when you just got through doing it. Actually the cam swap isn't that bad except for that stupid fan shroud
Thread Starter
Drifting
Joined: Jun 2000
Posts: 1,476
Likes: 1
From: Mt Juliet TN
Well it was my first cam swap I can't really say it was a problem with the cam. But I will say the machine shop that worked on my heads did say they've had issues with comp cams too and they go to the trouble of putting in soft springs to brake in the cam. Just food for thought.
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Thread Starter
Drifting
Joined: Jun 2000
Posts: 1,476
Likes: 1
From: Mt Juliet TN
I was very close to getting a roller cam but I need to do a gear swap. My 3.70 are too high for my tremec and torquey motor. Kind of wished I had now it would have taken all that pressure off of me in the initial startup.
Thread Starter
Drifting
Joined: Jun 2000
Posts: 1,476
Likes: 1
From: Mt Juliet TN
Originally Posted by Redshark6974
alot of reasons why comp cams have so much trouble with break ins...its all about choosing the right spring, and having everything adjusted and set.
Burning Brakes
Joined: Oct 2004
Posts: 984
Likes: 23
From: Florence SC
Originally Posted by TTop Tony
I guess I didn't adjust one of my valves right because I wiped out one of the lobes on my cam. Cylinder 7 exhaust. On the bright side I did get the other 15 right The cam lobe itself is almost flat thats how I figured it out I noticed it wasn't lifting as high as the other rockers
So its back to the drawing board. I decided to try a crane cam (278) this time. I don't think this was a problem with the comp cam I was using this being my first cam swap I'm sure I screwed it up but I had such a hard time tuning the carb with that lumpy idle I went to a crane with a 114 lobe center. Hopefully that will help. I've almost got the engine back apart but its slow going It is hard to get psyched when you just got through doing it. Actually the cam swap isn't that bad except for that stupid fan shroud
The cam lobe itself is almost flat thats how I figured it out I noticed it wasn't lifting as high as the other rockers So its back to the drawing board. I decided to try a crane cam (278) this time. I don't think this was a problem with the comp cam I was using this being my first cam swap I'm sure I screwed it up but I had such a hard time tuning the carb with that lumpy idle I went to a crane with a 114 lobe center. Hopefully that will help. I've almost got the engine back apart but its slow going It is hard to get psyched when you just got through doing it. Actually the cam swap isn't that bad except for that stupid fan shroud
I use GM's EOS in the first oil change of new cam break in and have had no problems. "GOOD CAMS GONE BAD"
Here's the thread: http://www.4m.net/showthread.php?t=139014
Please read the entire thread it makes even more sence towards the end.
Safety Car
Joined: Aug 2000
Posts: 3,711
Likes: 43
From: San Antonio TX
That Crane 278(#113801) with the wide 114LSA cam really favors good flowing heads, a manual transmission(or automatic with at least 2k stall), and a rear gear of at least 3.55. It has a fairly soft bottom end but kicks butt over 3k rpm. It also won't have nearly the lope, bottom or midrange of your old CC cam.
Thread Starter
Drifting
Joined: Jun 2000
Posts: 1,476
Likes: 1
From: Mt Juliet TN
Originally Posted by gerry72
That Crane 278(#113801) with the wide 114LSA cam really favors good flowing heads, a manual transmission(or automatic with at least 2k stall), and a rear gear of at least 3.55. It has a fairly soft bottom end but kicks butt over 3k rpm. It also won't have nearly the lope, bottom or midrange of your old CC cam.
Safety Car
Joined: Aug 2000
Posts: 3,711
Likes: 43
From: San Antonio TX
Originally Posted by TTop Tony
Really thats what crane suggested when I called? ....
Burning Brakes
Joined: Oct 2004
Posts: 984
Likes: 23
From: Florence SC
Originally Posted by TTop Tony
That was interesting and would have been usefull a couple of weeks ago
I used 10w30 oil. What oil type and weight should I have used and where do I get this gm eos additive?
I used 10w30 oil. What oil type and weight should I have used and where do I get this gm eos additive?Any General Motors should have or can get EOS (engine oil suppliment), again I've been using this oil additive just for startups with new cam breakins. I talked to Dennis at Reed cams and he told me, as he said in this artical, that I couldn't go wrong using straight 50 wt Valvoline racing oil as it contains the Zinc required for proper cam lubrication. (This is information was for our nascar super truck motor, I do not see any reason it would be differant for a street motor for breakin) the statement: "If your looking for a good break in oil or running oil try TORCO MPZ. moly and Zinc." might be worth looking into also I'm just not familiar with this oil. I think the Zinc is the key for proper cam breakin.
Thread Starter
Drifting
Joined: Jun 2000
Posts: 1,476
Likes: 1
From: Mt Juliet TN
Originally Posted by gerry72
It's a great cam, Tony. I'm using one in another car. It's just that it's not as strong as the CC 275 from idle to 3k rpm. Not that it lays down and dies but you'll notice the difference that four degrees LSA makes in the power band and the idle. It has a lope but it's not nearly as choppy as the CC. As I wrote, it's great on the top. Better get a shift light. Redline comes up real fast.
I'm glad it has some lope I did like the exhaust sound of the 275 just not the idle but I guess they go hand in hand. I really wish that 275 comp cam would have worked it had a great rpm range (2000 - 6000) although I have never really understood the recommended rpm range on the cam specs they don't seem to correspond to the desktop dyno readings at all. bracketshark
I'll look for that oil supplement and thanks for the info.
Team Owner
Joined: Sep 2001
Posts: 30,958
Likes: 0
From: Middletown Connecticut
Cruise-In IV Veteran
FWIW, I had some top end problems on my LT-1 about 500 miles into the new engine (with an xe268)
my first reaction was a wiped lobe thanks to everyone on the forum's problems..
had a bent rocker arm stud.
talk about a lucky break
my first reaction was a wiped lobe thanks to everyone on the forum's problems..
had a bent rocker arm stud.
talk about a lucky break