Header clearance

Discussion in '1970 - 1973 Specific' started by suds788, Feb 6, 2021.

  1. suds788

    suds788 New Member

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    Have 72 SS 402 Camaro. Installed hooker 2455 headers and the left side flange touches the floor board and the right side has about 3/8" clearance between floor board and flange. Headers bolted up no problem (after modifying the flanges to fit around arp head bolt heads) and are not touching anything on left side. Opps! not true, I might add I had to trim part of left side motor mount corner so as one tube wouldn't rub. Other than that nothing touching on left side what am I doing wrong? Any advice would be helpful.
     
  2. CorkyE

    CorkyE Veteran Member Lifetime Gold Member

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    What's condition of the body mounts? If original rubber, they can deteriorate and allow the body to sag.
     
  3. suds788

    suds788 New Member

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    The car is under restoration all body mounts are new rubber. The only change I've made to the car is I installed a T5 trans instead of the Muncie but even if I would lower the trans mount to get the header not to hit it wouldn't explain the gap difference between the two sides or would it?
     
  4. Twisted_Metal

    Twisted_Metal Administrator Staff Member Lifetime Gold Member

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    This isn't an unusual issue.
    Several other members have had problem with headers contacting the passenger side floor.

    Trans mount adjustment could give you some space.

    Are the headers bolted tight to the heads?

    Just a thought. (I've never had to do it because I have mid-length headers on a small block.)

    With a little brute force tweaking... You may be able to put a large prybar into the collector and force it downward to gain that little bit of clearance you need.
     
  5. suds788

    suds788 New Member

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    Yes bolts are all tight. Have another question don't know if posible, but where the motor mounts bolt to the frame is there any possibility one of the mounts might be higher than the other. Don't know as the holes for the mounts are fairly tight so there's not much room for movement when you tighten them down? Also, this is for you just for laughs Twisted I'm 68 how much force do you think i can exert on my back on the floor?
     
  6. Zspoiler

    Zspoiler Veteran Member

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    That would depend on what wrench you use .
     
  7. CorkyE

    CorkyE Veteran Member Lifetime Gold Member

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    I do remember many years ago, whittling down a 2x4, sticking it up the collector and doing some chin-ups. If all the body work is as it should be, really not an uncommon thing to do.
     
  8. lapedr

    lapedr Veteran Member Gold Member

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    I had the same problem on my 72 with SBC and auto trans, what worked for me was to cut the flange at the exhaust ports in 2 places along its length. The first cut is between the #2 and #4 cylinder, the 2nd cut is between the #6 and #8 cylinder. The cuts allow the header pipes to flex individually except for #4 and #6 which remain together, which in turn allows you to pull down on the collector flange under the floor board and gain clearance versus having to beat in on the floor board with a hammer.
     

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  9. 67johnny

    67johnny Veteran Member

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  10. suds788

    suds788 New Member

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    Thanks all for input always appreciate another set of eyes on a problem. Also thanks for the threads to look at. In my case yes it is a original big block car and according to the 1972 manual this year took the clam shell style mount pretty much a 1972 thing. I agree the ones your showing in the threads are also used and alot of people use them for header clearance but I wanted to stay as close as possible to original. Any way I just cut the top of the flange just above the bolt hole an this gave me about 1/4" clearance hope it's enough. Makes you wonder why hooker doesn't offset their flanges for chevy application seeing how people do have this problem with them. Thanks again for all the input.
     

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