exhaust diameter

Discussion in 'Technical' started by comet 75, Jan 7, 2004.

  1. comet 75

    comet 75 comet 75 swap 302

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    What exhaust diameter should I put on my comet V8 302, 600 cfm carb and intake??
     
  2. Corbin Johnson

    Corbin Johnson Member

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    It's primarily up to you. For a stock/mild 302, 2 1/4 inches is plenty big enough.
    -Corbin
     
  3. comet 75

    comet 75 comet 75 swap 302

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    thanks corbin
     
  4. Corbin Johnson

    Corbin Johnson Member

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    By the way, the engine looks good :) :D Very nice, I bet you'll love the 302!
    -Corbin
     
  5. Rob C

    Rob C Member

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    i would go with 2 1/2 or better. you never know you might want to put some hotter parts on that 302 this way your exhaust wont be for restrictive. jmo
     
  6. comet 75

    comet 75 comet 75 swap 302

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    thanks corbin I've pass all summer build it and I drove it 10 min to put it in a garage for winter so I wish summer come soon
     
  7. scott

    scott Member

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    i'm with rob c on this one...you're gonna lose a quater inch when they bend around the axle.
     
  8. CometGT1974

    CometGT1974 Gearhead

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    I"d go with mandrel bent tubing.
     
  9. comet 75

    comet 75 comet 75 swap 302

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    with 2 1/2 do I need to change my fuel tank cause I read that some people change for a mustang one to pass bigger exhaust ??
     
  10. courier11sec

    courier11sec Member

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    You should be able to get 2 1/2 through there, but changing the tankl still seems like a pretty good idea to me. I had to go through the space between the framerail and the spring to get 3" under mine and it didn't come out acceptable to me. I'm planning on doing either the mustang tank or a fuel cell in mine so I can do my tailpipes over and have something nice under there.
     
  11. riporter

    riporter Member

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    If your gonna run headers I would run 2 1/2 with an X-pipe crossover and 40 series flows,this will allow for unrestricted flow and the sweetest sound you have ever heard from an engine.
    A good exhaust man can get em out with no problem.
    Some 3" chrome tips make for a nice finish look
     

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