Keeping headers from cracking

Discussion in 'Manton Push Rods Top Alcohol Tech Questions' started by moparchris440, May 12, 2013.

  1. moparchris440

    moparchris440 Member

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    How do you guys keep your headers from cracking on a BAE blown Hemi. Currently I build them out of .065 and after a while they crack at the flange coming out of the head. These are not zoomies they are under frame headers that collect into 1 and come out the side on a 10.5 car. Ive tried supporting them and not supporting them, welding gussets from the flanges to about 1.5 inches down the pipes. Any input would be appreciated.
     
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  2. moldenhauerracing

    moldenhauerracing New Member

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    Get yourself a thermal sick from your welding supply,this depends on the temp which you need. Rose bud the joints (stress relieve) use the stick to achieve the given temp.The problem is the welded joint is too brittle,you must bring the joint back to where it was before welding.Hope this helps,DAVE
     
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  3. Mike Keener

    Mike Keener New Member

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    What rod are you welding with? If steel rod try a silicon bronze it will work better.
     
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  4. Kramer Metal Fab Inc.

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    Moparchris check your pms.
     
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  5. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    shake

    i have noticed a positive correlation between tire shake and header cracks.

    so just don't shake the tires, you'll be good.
     
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  6. jay70cuda

    jay70cuda Member

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    Hahaha. Now that's priceless. I have found by squishing the tube down and forcing it inside the flange , takes some work but if you do that and then mig weld, yes mig weld the flange on the outside and use the tig torch and weld the inside of the flange I have gotten about a years worth of runs before I seen cracks. However you should be looking every weekend after racing for cracks. These are violent machines in the 2 step , everything fatigues over time.
     
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  7. PROMOD63

    PROMOD63 Member

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    mig mig mig !!!

    we had a set of headers that we thought we were going to have to replace that were tig welded at the flanges and cracked almost every time we too it out we kept having them retiged each time last year in a rush to get to the races we took one off and mig welded it where it had cracked so now we have one side miged and one side tiged so over the winter i pulled them off and checked them for cracks and built braces for them that hooked the tubes together as well as to the chassis but left the flanges alone.....first time out guess what the tiged side broke loose again but the mig side was great so we took the tiged side and mig welded it and wala if any of you were at tulsa you can attest to the fact we shook as fiercly as it gets and no cracks my opinion is that a tig weld dosent connect enough area between the tube and the flange
     
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  8. overkill69

    overkill69 Member

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    Tig

    My Chevy stainless set never cracked at flanges but everything else broke. I adapted mild steel flanges for bae and used silicon bronze with big fat beads...haven't hit it yet.
     
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  9. turbo69camaro

    turbo69camaro Member

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    I have a few ideas i would like to try including .083 wall tube for the first 4-6'' maybe 4130 flanges different bracing.... looking for a Ginny pig lol
     
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