diy manifold advice needed
#1
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Right, as some of you know I have the ebay manifold. I braced it as we all say one should and the damn thing has cracked anyway. In fact I am pretty sure too much preload on the brace is what did it. All the same there is no point in me using the same thing again, so I have been to talk to the local fabricator and he has offered to give it a shot at a damn good price (180 GBP) on the condition I supply the turbo and head flanges and the old manifold to use as a pattern (so I can use the existing d/p). This one will of course be made of mild steel and a damn sight thicker stuff.
So here are my questions, I have found the turbo flange on eBay for cheap in 10mm thick steel. Its on the way already. for the cyl head flange I got nuthin. I was thinking of cutting up the old stock manifold to re use the flange from it? is that thick enough? He tells me that he can have another laser cut using the stock one as a pattern. Would that be the way to go? I am sure a thicker flange is better (10mm again?) but would the stock piece be enough, as I would rather save the money if it is not needed. Thoughts?
and what thickness steel should I be looking for for the runners? I have heard "shedule 30" thrown around but that fell on deaf ears with him (I am in the UK). any idea how thick it needs to be? I am hoping to get something thick enough so that I will never have to dick with this again.
Any and all advice is welcome. Pics would also be great. Thanks gents......
So here are my questions, I have found the turbo flange on eBay for cheap in 10mm thick steel. Its on the way already. for the cyl head flange I got nuthin. I was thinking of cutting up the old stock manifold to re use the flange from it? is that thick enough? He tells me that he can have another laser cut using the stock one as a pattern. Would that be the way to go? I am sure a thicker flange is better (10mm again?) but would the stock piece be enough, as I would rather save the money if it is not needed. Thoughts?
and what thickness steel should I be looking for for the runners? I have heard "shedule 30" thrown around but that fell on deaf ears with him (I am in the UK). any idea how thick it needs to be? I am hoping to get something thick enough so that I will never have to dick with this again.
Any and all advice is welcome. Pics would also be great. Thanks gents......
#4
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Also, i've never heard of schedule 30, only sched 10, 40 and 80. Schedule 10 works pretty well and is super light. Schedule 40 is heavy but much thicker.
The problem with pipe sizing is that schedule 10/40 etc doesn't have a specific inner or outer diameter so I dont know how else to describe them. Wall thickness?
#5
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Schedule does determine wall thickness, but in a roundabout way. It's actually a ratio of the working pressure over the material's critical stress, and the thickness is then calculated using the hoop stress equation.
This basically means that a given schedule of pipe is rated to hold a certain amount of pressure relative to failure of the material. This is where material selection (stress properties) and design parameters (flow, weight, pressure, cost) meet geometry (diameter, thickness).
The higher the "schedule" the safer it is at any given pressure. This is entirely logical since you can see how much thicker the walls are.
I know that there are quite a few schedules out there, but not sure about 30.
EDIT:
Sure enough, there is a schedule 30, and a 5, and a 160...
http://www.allsteelpipe.com/Pipe-Dim...ghts-Chart.pdf
I'm sure they're hardly used, but the callout is there.
This basically means that a given schedule of pipe is rated to hold a certain amount of pressure relative to failure of the material. This is where material selection (stress properties) and design parameters (flow, weight, pressure, cost) meet geometry (diameter, thickness).
The higher the "schedule" the safer it is at any given pressure. This is entirely logical since you can see how much thicker the walls are.
I know that there are quite a few schedules out there, but not sure about 30.
EDIT:
Sure enough, there is a schedule 30, and a 5, and a 160...
http://www.allsteelpipe.com/Pipe-Dim...ghts-Chart.pdf
I'm sure they're hardly used, but the callout is there.
#6
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Sorry guys, 30 was just a number I pulled out of thin air. All I meant is that you boys are always talking in those terms and not actual wall thickness. Doesn't matter really I'll just tell him "******* thick" and see what I end up with.
I did do a search for- diy manifold - but only got 6 threads with that in the title. Manifold alone of course returns hundreds. I'll try crosso g it with your user names to see what you guys did tonight. Thanks for the help.
I did do a search for- diy manifold - but only got 6 threads with that in the title. Manifold alone of course returns hundreds. I'll try crosso g it with your user names to see what you guys did tonight. Thanks for the help.
#7
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Sorry guys, 30 was just a number I pulled out of thin air. All I meant is that you boys are always talking in those terms and not actual wall thickness. Doesn't matter really I'll just tell him "******* thick" and see what I end up with.
I did do a search for- diy manifold - but only got 6 threads with that in the title. Manifold alone of course returns hundreds. I'll try crosso g it with your user names to see what you guys did tonight. Thanks for the help.
I did do a search for- diy manifold - but only got 6 threads with that in the title. Manifold alone of course returns hundreds. I'll try crosso g it with your user names to see what you guys did tonight. Thanks for the help.
#9
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Had a look at all three, very nice work on every count. I wont be doing the work as I have neither the skill or the tools, and with the car sounding the way it does I don't have time to learn. Still at least now I know what to tell him I am after. I was planning to get a 10mm head flange made, but I dug out the old stock mani tonight and it looks like that is what it has. So back to plan A. I am going to try and grind out the welds to remove the runners, and just have him use that. Mild steel is mild steel right? anyone see a massive problem with this?
It will of course take time, but I have a week off beginning of june, so I am going to take the car off the road then (if it makes it that long) and pull the eBay manifold off for him to use as a pattern. So I have until then to dick around getting the orig. mani apart.
So am I crazy?
It will of course take time, but I have a week off beginning of june, so I am going to take the car off the road then (if it makes it that long) and pull the eBay manifold off for him to use as a pattern. So I have until then to dick around getting the orig. mani apart.
So am I crazy?
#12
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Yeah, I gotta be honest man, If I could get it for $30 and have it here in 3 days I would. Unless you are doing it just to say you did, and that I totally understand, just order one. If I did it would end up costing me $60 or so and most likely take 2 weeks to get here.
For some damn reason everytime I order parts from the states they wait FOREVER to even mail it. Its driving me nuts. I ordered a fuel line kit for my VW bus over a month ago and it still hasn't turned up. I have already paid the credit card bill for Christs sake! and this is from a well respected company. And I am even American so the phone calls all go smoothly as I speak the same language. But every time its the same old song and dance "yeah we are going to get that right out, but the international shipping is slowing it down". I have mailed **** to and from England and it is no different. At this rate I could have had it sent to my dad and have him send it on. In future I will.
Sorry, rant over...grumble grumble....... bitch, bitch.......
For some damn reason everytime I order parts from the states they wait FOREVER to even mail it. Its driving me nuts. I ordered a fuel line kit for my VW bus over a month ago and it still hasn't turned up. I have already paid the credit card bill for Christs sake! and this is from a well respected company. And I am even American so the phone calls all go smoothly as I speak the same language. But every time its the same old song and dance "yeah we are going to get that right out, but the international shipping is slowing it down". I have mailed **** to and from England and it is no different. At this rate I could have had it sent to my dad and have him send it on. In future I will.
Sorry, rant over...grumble grumble....... bitch, bitch.......
#14
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This is what you want for the piping.
1-1/2" sch10 long radius butt-weld 90° elbow 304/304L
They're made in Taiwan, so should be distributed internationally, but good luck finding this price anywhere else.
There are short-radius els in 316 if you get in a packaging bind, but they are buck$.
1-1/2" sch10 long radius butt-weld 90° elbow 304/304L
They're made in Taiwan, so should be distributed internationally, but good luck finding this price anywhere else.
There are short-radius els in 316 if you get in a packaging bind, but they are buck$.
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