No problem, I know that sucks having to keep pulling it! When I was turbo I always ran mild steel 16 gauge as it was cheap and reliable and no brace required because wall thickness was like .065". But alas my exhaust system probably weighed at least twice what yours does and certainly was not as pretty!

I really dont care much about it looking nice.. I really just want to be able to drive the thing without worrying about anything going wrong. I wouldnt be opposed to having an exact duplicate made in a thicker walled piping BUT I highly doubt Artech would eat the cost of that. I'm sure the materials are more expensive and the labor time would be long.

How did we conclude this is thin walled? Might it not be 16 GA SST?

I measured it with a micrometer.

No, I don't know what gauge it is actually, maybe the guy who made it can chime in? Or the OP can measure it and post. Actually a good point, if it IS 16 gauge then damn, I don't know how you keep breaking it!

Abe just got back to me so now I just have to pull the pipe back out and get it shipped over to him

DP Is out once again... Off to Abe tomorrow!

Installed/ Uninstalled pics for Artech. No contact with anything anywhere :-/

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You need a god damned flex pipe and brace.

Dann

Well I guess I need a second flex pipe lol... And I definitely will be adding a brace as soon as I get it back

I said you need those 2 things because I know you don't have those 2 things.

Shouldn't we be concerned that it's failing through the weld?

thats standard failure mode.

Look at the welds in the photo on the downpipe, they are close to textbook perfect. Abe is clearly very skilled.

He has a flex pipe in the downpipe and the wastegate pipe.

That I do sir

Really, that's weird. Every welding specification I've ever read requires that the material fail in the base metal and not in the weld.

When I worked at Honda we did lots of testing for this exact thing, the tensile specimen was always required to fail in the base metal. If the specimen failed in the weld or in the HAZ then the test was considered a failure.

I don't doubt Abe's skills at all. But in my experience, a failure straight through the weld bead is a big no-no.

the way it split makes me think there's stress there, like the bend needed to open up a bit.

Agreed. I'm no TIG guy but looks like it was just melted together/no filler, and undercut in the process, causing a weak weld.

Then why did it also fail the second weld with a nice fat filler mound there.

This is scary. I've welded a bunch of downpipes with no filler, no reinforcements, no flexes (basically any 'street car' setup i've done), and I'm a far inferior welder to abe, while using inferior material (vibrant bends instead of beautiful steam pipe bends).

SO something's off with the car, not the pipe. What that is, I dunno. :dunno:

How buzzy is your car? Running a chinese flywheel/clutch?

Its not buzzy at all... Smooth actually. Its a FM Stg1 clutch with OEM flywheel. I really dont know what in my car would cause it to keep happening. The downpipe will arrive to Abe on Friday and he will have it headed back in my direction early next week. He is going to be adding a slip joint over the cracked weld to reinforce that joint.

The only thing I noticed when removing the downpipe yesterday was that the exhaust seemed to be pulling down on the back side of the downpipe. I'm assuming that was putting stress on the weld that cracked and thats why it split. I fully plan to add a brace and see what happens this time.

In other news, i'm now a pro at pulling my downpipe. Literally had it out in like 20 mins yesterday compared to 2 hours the first time (Granted, the anti-seize was still fresh on the downpipe hardware)

That shit gets everywhere but it's worth its weight in gold.

I don't know. In one of his pics (this one: http://i119.photobucket.com/albums/o...pszeiucefg.jpg ), it looks like the 2nd weld was not all the way around, there is a spot (that failed) that is still undercut in the pics. Perhaps (again, I don't TIG much so don't know much about TIG) this spot failed and then the crack propegated.

But I dunno. Seems to me something is putting really high stress in that spot. Hence why I recommended a brace.

Random though, but if his EGT's were really high for some reason, would that contribute to this failure?