Hello. I'm an aerospace welder and fabricator in the middle of building a car. I'm coming up to the manifolds soon. I've built headers before but not turbo manifolds. I'm using schedule ten pipe as opposed to tubing since the thicker material resists cracking better under repeated heat cycles. Now, my engine has oval ports. I know with tubing you just squish it into an oval. But can you do that with schedule ten? I haven't worked with it much before
I have a buddy that has built several sets. Here's his response to your question. "Would not recommend that, find out what the port dimensions are - what size engine and turbo I can tell you about what size schedule 10 to use." Here's a few pics of his work.
For starters, that's some damn good looking work. The size of the pipe here isn't really the issue though. It's the port shape The port is oval the pipe is circle. I'm just wondering if the pipe can be squished into an oval like people have always done with tubing in this same situation
His reply. If he purges it 16 ga will be fine as long as the turbo is supported by a mount and proper double slips or flex joints are used. To large of pipe will make a lazy turbo was my point on asking about sizes - I would not oval schedule 10 pipe myself but i suppose you could try it and see if it broke Run a smaller 16ga stainless that's easily formed. Like these square to round ones in the attached pic.
Is he using 304? Just figured I'd ask. I've read that thinner 304 has a tendency to crack under repeated heat cycling. Which is what led me to the schedule ten stuff. If 16 gauge is fine though, that's a relief on my wallet I suppose. And the manifolds are for a vh45de. It's a 4.5 liter dohc v8. I don't have the port size handy at the moment though.
Yes 304 if the turbo is supported by Its own mount, proper double slip or flex is used on the hot side pipeing so there is minimal stress on the headers 16/14ga will heat cycle just fine - yes they will crack if the welds are poor or if there is stress on them