Steampipe manifold failure
#21
I don't have pics, I sold the manifold and it split in his possession. But, it basically looks like it crumbled along the seam, and eventually the material started chipping away until it started leaking.
#23
My artech manifold completely failed after one track day, made it through a handful of autocrosses, and 4 1/2 25 minute track sessions. I gave it back to him for repairs and he added small gussets and the weld is visibly larger. Haven't got the car back together to see how it works out, but I'm less than confident in it lasting long.
#24
So do I have reason to be concerned about running an artech manifold on the track? Is this common? I've probably got a while before I make it on the track and a lot longer until I'm anything approaching fast, but I do have aspirations of winning all the HPDE. These look like the sort of failures that would be a serious bummer on track day.
#25
So do I have reason to be concerned about running an artech manifold on the track? Is this common? I've probably got a while before I make it on the track and a lot longer until I'm anything approaching fast, but I do have aspirations of winning all the HPDE. These look like the sort of failures that would be a serious bummer on track day.
#30
My original AF manifold lasted all of two days before the EWG broke off. While it was back getting that fixed, Tim noticed several other cracks (this was circa 2009). He added the diamond gussets that have become commonplace among manifolds shown on this forum since then. I ran that same manifold with the additional gussets for all of 2010 and most of 2011 before mothballing the car and it was perfectly reliable.
At least you're using sch40. I've seen other vendors swear up and down that their 304SS Sch10 manifolds hold up just fine on track. The more you know...
At least you're using sch40. I've seen other vendors swear up and down that their 304SS Sch10 manifolds hold up just fine on track. The more you know...
#31
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My AF mani has seen probably 15 total track days, and I beat on it pretty hard. Only issues I've had were one mani -> head nut coming loose, and the EWG bellows failed. Has the diamond gussets Andrew mentioned.
#35
Original manifold doesnt look like brittle failure. Just fatigue. Getting the two mixed up is common as fatigue failures look like brittle failures, but of course mild steel is not brittle. I'd say you had a crack start at the section with low penetration and just propagate with fatigue. A lot fo fatigue can happen very fast on a racecar spending a bunch of time at the upper rpms. To avoid this you could gusset the crap out of it. But getting some better welds on there would help; no mistruck arcs, nominal penetration, no sharp edges or grooves in the pieces after weld prep, etc. Basically work towards aerospace level welding. Using 321, using gussets, ect all give you a larger margin on this, and let you get away with having bigger weld gaps and lower quality welds, and there's some threshold here where no matter how good you weld the material is too thin or mechanically deficient.
#40