cam timing question

Discussion in 'Technical' started by JHodges, Apr 16, 2010.

  1. JHodges

    JHodges thumper

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    I have a comp cams extreme energy cam and lifters. I will be putting it it a 351 with c9 heads. On my comp double roller timing set it says that the cam could be installed 2 degrees retarded strait up or 2 degrees advanced. I was planning on advancing it 2 degrees but figured I would get some opinions. I do not have a degree wheel so I can't degree the cam
     
    JHodges, Apr 16, 2010
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  2. PaulS

    PaulS Member extrordiare

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    Advancing the cam will give you more low end but take away about half as much on the high end - retarding it will do the opposite. You need to have a degree wheel to check the timing of the cam - there is no substitute for that. You also have to find TDC of your crank to be sure that the cam is timed to the crank properly - you will need either a dial indicator or a positive stop to find TDC correctly.
    Get the tools or rent them - this is probably not the last engine you will build.
     
    PaulS, Apr 16, 2010
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  3. baddad457

    baddad457 Member

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    Just run it straight up. I always do and have never found the need to do otherwise. TDC is easy to find with the crank, what's harder to do is figure where to run the cam in relation to that for the optimum results. Even then, unless you degree each and every cylinder to see where they are in relation to the crank, you're shooting in the dark just doing one cylinder. There are so many variables here that unless you have access to a dyno to run it in various settings, there's no garantee that even if you do run it advanced 2*, how will you know it would be better set any other way ? So I just run em straight up and don't worry about it.
     
    Last edited: Apr 16, 2010
    baddad457, Apr 16, 2010
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  4. bmcdaniel

    bmcdaniel Senile Member Supporting Member

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    Always degree a new cam and/or timing set, it's the only way to know what you have.
     
    bmcdaniel, Apr 16, 2010
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  5. brainsboy

    brainsboy Member

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    As mentioned you need to degree the cam in first. You can buy 3 of the same cams and all three could be different which is why you have to use a degree wheel to find out where your cam is to begin with. As for advancing or retarding the cam I wouldnt bother with it. Its not as simple as getting more low end or top end. After market cylinder head port sizes combined with stroking, and longer rods are all reasons to change the cam timing, but it takes a lot of math and time to figure it all out. Unless your bracket racing in a certain class then just degree the cam normaly and be done with it.
     
    brainsboy, Apr 17, 2010
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