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what cam??

Discussion in 'Early CJ5 and CJ6 Tech' started by jeepcj, Oct 7, 2011.

  1. Oct 11, 2011
    Corveeper

    Corveeper Member

    Chanute, Kansas
    Joined:
    Jul 29, 2005
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    817
    Is this what we’re talking about?

    http://www.compcams.com/Technical/DynoSheets/XE268H-10_001.asp

    If so that’s a pretty good looking cam sheet but it might have a bit more lift than you have valve springs to handle. If you’re going to go this route you might check into the manufacturers recommended springs and retainers. They should offer some that will give you the correct stack height and spring rate to handle their cam profile.
     
  2. Oct 11, 2011
    Corveeper

    Corveeper Member

    Chanute, Kansas
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    Jul 29, 2005
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    817
  3. Oct 11, 2011
    jeepcj

    jeepcj Member

    cincy, Ohio
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    Aug 23, 2009
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    601
    yes that was the 268H cam. If that may be a bit big then I will probably get the cam that is in it now. I thought that the 327's with the 462 heads had 10.1 compression and could take that cam. but I dont know much about the engine building stuff so I'll take you word for it. I did run the manifold numbers (3872783) it is a 66 corvette 300hp manifold, thats kinda cool. that shoots the previous owners horse power claims of 400 right the window. lol
    Its a jeep anyway not a hot rod, but I do love that power. thanks for your help..
     
  4. Oct 11, 2011
    Corveeper

    Corveeper Member

    Chanute, Kansas
    Joined:
    Jul 29, 2005
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    The problem is in the valve springs and retainers. Since a stock cam had .410" lift I wouldn't feel safe in saying they could handle .480" without binding, which would knock cam lobes flat again. The rest of your engine should handle a cam like that just fine and would make good power with it.
     
  5. Oct 12, 2011
    jeepcj

    jeepcj Member

    cincy, Ohio
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    Aug 23, 2009
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    OK, I dont want to get into doing all that. changing the cam is intemidating enough. I will just replace it with the same type cam. thanks I was hopeing you would get in on this thread. I'll let ya know how it turns out, should be about 2 weeks. That edelbrock cam you used looks a little tamer with 442 lift. ?????? hmmmm I wonder. never mind, I just need to stop now, and just replace it with the same and be done. thanks for you help
     
    Last edited: Oct 12, 2011
  6. Oct 12, 2011
    Corveeper

    Corveeper Member

    Chanute, Kansas
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    Jul 29, 2005
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    No problem, glad to help.
    When I have more time I want to talk to you more about installation, setup and break-in. Its all very critical because getting any step slightly wrong means knocking a cam lobe flat and doing this all over again.
     
  7. Oct 12, 2011
    jeepcj

    jeepcj Member

    cincy, Ohio
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    Aug 23, 2009
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    That would be great!! I can use all the help I can get. I only know one person that has put a cam in (so he says) he watched me take this one out, but my other buddys consider him a shadetree, I don't know him very well, just an aquaintance, but he seems to know, so im kinda on my own. I will let him watch me but thats about it. thanks alot!
     
  8. Oct 12, 2011
    Mike S

    Mike S Sponsor

    Cameron Park Ca.
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    While you are at the chore of replacing the cam, and lifters, dont forget to replace the sprockets and drive chain as well. Chances are pretty good that they are worn out.

    I personally like a double row roller chain.

    Also, you are going to have to drop the oil pan to get the timing gear cover off. While you have the pan off, check a rod bearing or two------you may find metal flakes in there from the cam and lifter wear. If you do find any metal embedded in the bearings, that is a clue you need to look deeper. Replacing the oil pump is easy at this time, and good, cheap insurance.
     
  9. Oct 12, 2011
    Corveeper

    Corveeper Member

    Chanute, Kansas
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    See that’s the thing. It’s assumable that cam and lifter material has circulated the engine a few times, meaning it’s more than likely in the crank. The proper way to do this is to break down the engine, flush or have the crank flushed, and then reassemble the engine with new bearings, rings, gaskets and seals. You’re kind of rolling the dice by not breaking it all down and cleaning it up.
    That said I’ve gotten away with it before, just know the risk you’re taking.
     
  10. Oct 12, 2011
    jeepcj

    jeepcj Member

    cincy, Ohio
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    never even thought of where the metal material went, I will take the pan all the way off and see what I see. The timing chain is getting replaced, it was very loose. It is the double chain though. thanks, Ill keep you posted.
     
  11. Oct 15, 2011
    trickpatrick

    trickpatrick Done? LOL

    North Idaho USA
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    Nov 29, 2006
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    Been going through this to.
    The bottom line is if your not going over 5000 rpm.
    An rv cam or a truck cam if you will,, is perfect.
    the reality is you want all the bottom end torque you can get.
    You will have all the HP you will need.
    Remember it's a SBC in a jeep its allready over kill:)

    It's hard to get hotrod propaganda ie:go big.. out of the decision.

    I called Erson cams and told them my setup and they were more than helpful..

    Flat tappet cams need special oil to be broke in properly
    Todays oils will kill it if you dont, google it, it's critical now..:(

    Rick
     
  12. Oct 15, 2011
    w3srl

    w3srl All-around swell dude Staff Member

    Port Orange, FL
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    Nov 6, 2002
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    4,275
    :iagree:

    Even a mild 300HP SBC in a short-wheelbased Jeep can be exciting all by itself! :shock:
     
  13. Oct 16, 2011
    jeepcj

    jeepcj Member

    cincy, Ohio
    Joined:
    Aug 23, 2009
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    Yes, ive been reading a lot about cams and the break ins, It seems that comp cams have a bad rep right now. Problems with soft lifters and lobes on cam going flat. I was going to go with them but, edelbrock, or erson are probably my choices now. Like trickpatrick said, a SBC in a jeep is a lot on its own, I think I am just going to replace it with at least whats in it, or look a cam for lower torque, I have thought about the engine size in a jeep, I have driven the 304 cj's and they are like what.. 125, 150 horse, this is probably more than twice that, so again like trickpatrick said, Ill have plenty of power at any given time. I want to play on the street a little but off road is my main thing. It will be about a week, so I will let you know what I get and how it is. any sugestions between now and then will be much appreciated. thanks
     
  14. Oct 16, 2011
    Heatseeker

    Heatseeker Member

    Calaveras...
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    Oct 2, 2009
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    The prob might not be Comp's. A few years back, most of the oil manufacturers removed the zinc content from engine oil. It seems it was shortening the lives of some catalytic converters. Apparently, flat tappet cams needed the lubricating properties that the zinc added, more so than the roller cams.

    I've changed many flat tappet cams in friend's boat engines in the last three years. A couple of them were newly installed and flattened with the first couple of hours of run time, after proper break in.

    Use an oil that lists zinc on the label (like Valvoline racing oil) and the problem will not recur.
     
  15. Oct 16, 2011
    Farmer Mike

    Farmer Mike Member

    Butte City, Ca
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    I'm sure it was a jet and not a v-drive!! R)
     
  16. Oct 16, 2011
    Heatseeker

    Heatseeker Member

    Calaveras...
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    You betcha ;) !

    Farmer Mike eh, maybe AKA Kindsvater Flat on another board??? Just wondering.
     
  17. Oct 16, 2011
    Corveeper

    Corveeper Member

    Chanute, Kansas
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    Its not just Comp Cams, pretty much all flat tappet cam manufacturers have been having problems.
    While it is a good idea to run a bottle of cam breakin additive in the oil for breakin and even for the first few hundred miles my opinion is that the best way to ensure a happy cam with a long life is proper setup.
    Make sure you get the lifters lashed in properly and most importantly rotate the engine around by hand watching each lifter to ensure that as it lifts its also spinning.
    Remember this picture I posted earlier?

    This is a perfect demonstration of why cam lobes go flat. The lifter, for whatever reason, stopped spinning.
    Notice that the pair of lifters towards the bottom have a nice round wear pattern to them? Thats the way they're supposed to look.
    Notice the pair in the middle has a straight wear pattern? They were headed the same direction as the top pair of lifters with a little more run time.
     
  18. Oct 16, 2011
    Heatseeker

    Heatseeker Member

    Calaveras...
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    So true. I forgot to mention that. Crane Cams, who I've been told produces 80% of all cam blanks used by other cam manufacturers, almost went bankrupt over this deal.
     
  19. Oct 16, 2011
    jeepcj

    jeepcj Member

    cincy, Ohio
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    thanks for all the help and tips, I have been googling, as things get brought up and have found lots of good info.
     
  20. Oct 16, 2011
    Farmer Mike

    Farmer Mike Member

    Butte City, Ca
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    LOL!! Thats me.
     
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