Down to 2 cams... Which one?

Discussion in 'Engine Topic' started by 71cmro, Feb 16, 2011.

  1. 71cmro

    71cmro Veteran Member

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    Dec 3, 2003
    Beavercreek, OH USA
    Probably not much difference in them but I figured I would ask those that know. Thanks.

    Comp Cam 268h vs Comp Cam 270h

    Engine specs
    350 4 bolt main
    Eddy Vortec Intake
    Full length headers
    4bbl Quadrajet

    Heads
    Vortec cast iron 170cc Intake ports
    64cc combustion chambers
    1.940" Intake/1.5" Exhaust
    .475" max lift
     
  2. 5spd540

    5spd540 Veteran Member Lifetime Gold Member

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    Sep 19, 2009
    Guyton, GA
    the270 sounds better but the 268 is mire street friendly
     
  3. 5spd540

    5spd540 Veteran Member Lifetime Gold Member

    12,256
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    Sep 19, 2009
    Guyton, GA
    What do you have for a converter
     
  4. Cardinal

    Cardinal Veteran Member Lifetime Gold Member

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    Jun 22, 2003
    Endicott, NY
    I am a die hard fan of the Qjet BUT it HATES big cams as it requires good vacuum at idle. So, I would choose the 268H because it is going to produce slightly more vacuum at idle.

    We've run that cam on a bunch of stock engines and quite honestly, I think it's about the best street cam you can use.

    Remember: less is more ESPECIALLY with cams. The BIGGEST mistakes are putting too big a cam and TOO big a carburetor. It's know as the BIBS: bigger is better syndrome. EX: if a 600 carburetor is good, then a 1150 HAS to be better. NOT!
     
  5. onovakind67

    onovakind67 Veteran Member

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    Jul 8, 2001
    Fairfield, CA
    What characteristics of a Q-jet require high vacuum at idle?
     
  6. Todd80Z28

    Todd80Z28 Moderator Staff Member Lifetime Gold Member

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    Jun 11, 2002
    Northern VA
    Both are single pattern, and IMO, both are wrong for the Vortec heads.
     
  7. mrvedit

    mrvedit Veteran Member

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    Jun 12, 2009
    Ann Arbor, MI
    You might consider the XE268H which is dual pattern. However it has .520" of valve lift. I don't have experience with Vortec, but I understand it is easy to modify Vortec heads to support that much lift.

    Just checked - the 270H has .51" of lift, while the 268H has only .454 of lift.
     
    Last edited: Feb 16, 2011
  8. onovakind67

    onovakind67 Veteran Member

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    Jul 8, 2001
    Fairfield, CA
    The 270H has only .470" of valve lift with 1.5:1 rocker arms.

    http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=78&sb=2
     
  9. 71cmro

    71cmro Veteran Member

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    Dec 3, 2003
    Beavercreek, OH USA
    Please explain. Many folks on here recommended these cams for vortecs last year when I bought them.
     
  10. 71cmro

    71cmro Veteran Member

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    Dec 3, 2003
    Beavercreek, OH USA
    Stock converter. From my research both will work with the stock converter but the 270 requires a 4bbl carb and headers which I have.
     

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