X-Force NA6 B6 Header Weld Cracks

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decitex64
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X-Force NA6 B6 Header Weld Cracks

Postby decitex64 » Tue Aug 11, 2015 1:03 pm

My six year old X-Force s/s header has cracked twice this year at the same weld point; approx. 50cm. or so back from the header flange which bolts onto the cat.
Exhaust specialist is telling me that the s/s is getting brittle from heating / cooling...
Car gets tracked once a month on average.
On both occasions this year the same weld has cracked after Winton track days.
Engine mounts are ok.
Do I tig weld again and chance it cracking for a third time or bite the bullet and replace with some mild steel headers?
Genie mild steel 421 headers are selling for $339 here in Melbourne.

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Re: X-Force NA6 B6 Header Weld Cracks

Postby NitroDann » Tue Aug 11, 2015 3:08 pm

Your exhaust guy is inexperienced in proper performance parts, or lazy. He can clean the weld with a wire wheel, or if he has one, an electronic stainless cleaning machine, then we welds your cracks and over the top he welds diamonds of stainless to reinforce. Here see these Racing Beat headers.

Image

They do this from the factory.

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Re: X-Force NA6 B6 Header Weld Cracks

Postby slug_dub » Tue Aug 11, 2015 3:38 pm

It could be worth getting a flex joint fitted further down to help with that... The cracking is just as likely to be due to movement and vibration stresses isn't it?
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Re: X-Force NA6 B6 Header Weld Cracks

Postby NitroDann » Tue Aug 11, 2015 3:50 pm

If it doesn't have a flex the whole thing is fail.

It has to have one.

A flex will not fix this issue though, welds crack around collectors and major merge point on stainless, period. They need additional strengthening. The Racing beat headers crack aftera ccouple of years but they don't break or fail because of the extra diamonds added.
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decitex64
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Re: X-Force NA6 B6 Header Weld Cracks

Postby decitex64 » Tue Aug 11, 2015 5:52 pm

Thank you for the advice.
I will remove the header, clean the weld properly, weld the crack and over the top weld diamonds of stainless to reinforce.
It will also be my cheapest option.
Shall revert with feedback after Sandown early next month.
Cheers


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