DIY manifold
10-08-2012, 08:18 PM
#141
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Anyone here tried out BMC Race Products?
Mazda 18L Header Manifold Flange Standard - 1/2" mild
Model #: MAZDA18LHF
Our Price: $37.50
Mazda 18L Header Manifold Flange Standard - MAZDA18LHF - BMC Racing Products
T25 Turbine Inlet - 1/2" mild
Model #: T25TI
Our Price: $14.50
T25 Turbine Inlet - T25TI - BMC Racing Products
Unfortunately they do not offer the BP head flange in their "Premium" profile. According to BMC: "Premium flanges are port matched from 1 1/2 inch Schedule 40 Pipe to the head port. Reliefs are machined on the flange to help isolate the heat from the manifold."
What cooks my noodle is these guys don't appear to sell a standard Garrett 5 bolt outlet flange
BMC wants $7.00 shipping to the left coast so that's $59.00 for both flanges in 1/2" mild. Weir wanted $62.32 shipped for the same thing, but in 3/8" mild.
I'll let you guys know how they look when they get here
Mazda 18L Header Manifold Flange Standard - 1/2" mild
Model #: MAZDA18LHF
Our Price: $37.50
Mazda 18L Header Manifold Flange Standard - MAZDA18LHF - BMC Racing Products
T25 Turbine Inlet - 1/2" mild
Model #: T25TI
Our Price: $14.50
T25 Turbine Inlet - T25TI - BMC Racing Products
Unfortunately they do not offer the BP head flange in their "Premium" profile. According to BMC: "Premium flanges are port matched from 1 1/2 inch Schedule 40 Pipe to the head port. Reliefs are machined on the flange to help isolate the heat from the manifold."
What cooks my noodle is these guys don't appear to sell a standard Garrett 5 bolt outlet flange
BMC wants $7.00 shipping to the left coast so that's $59.00 for both flanges in 1/2" mild. Weir wanted $62.32 shipped for the same thing, but in 3/8" mild.
I'll let you guys know how they look when they get here
Last edited by EO2K; 10-08-2012 at 08:29 PM.
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10-08-2012, 08:41 PM
#142
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That premium option would be awesome. I'd call them and see if they'll do it. If I knew what I know now about building a manifold, I would've definitely sprung for that additional option.
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10-08-2012, 08:49 PM
#143
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That's not a bad idea actually. I'll give them a call tomorrow morning and see if they are willing to make the change. They probably just cut these things to order anyway seeing as how they are on a CNC.
Edit: Just sent them an email, I'll report back with any response.
Edit: Just sent them an email, I'll report back with any response.
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10-18-2012, 03:37 PM
#147
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McMaster-Carr Mild Steel Weld Els seem to be the norm. Also available in stainless if that's your thing.
http://www.mcmaster.com/#catalog/118/75/=js03tr Steel Pipe Fittings & Pipe
Example:
Long Radius 90°
Standard Sch 40
1 1/2 "Pipe Size"
0.145" wall thinkness
2.25" radius
PN 43425K151
McMaster-Carr
FYI: Internal diameter ends up being 1.6" w/Sch 40, that's why it says "Pipe Size" in quotes. Same part in Sch 80 has actual 1.5" ID
http://www.mcmaster.com/#catalog/118/75/=js03tr Steel Pipe Fittings & Pipe
Example:
Long Radius 90°
Standard Sch 40
1 1/2 "Pipe Size"
0.145" wall thinkness
2.25" radius
PN 43425K151
McMaster-Carr
FYI: Internal diameter ends up being 1.6" w/Sch 40, that's why it says "Pipe Size" in quotes. Same part in Sch 80 has actual 1.5" ID
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10-18-2012, 05:24 PM
#149
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I honestly don't know, I've never built one before! I was just going off what BMC said about their particular flanges. This started as Baron340's thread and I believe he did Sch10 SS? Stein, Wayne_curr, 18psi and others have DIY'd, but only Stein linked his in this thread (post #13.) 18 has like 6 build threads so good luck finding his. The Stein/Wane_curr/baron340 manifold is basic enough that even a caveman like me should be able to blunder through it.
So to make it easier on myself, I decided to take advice from those before me and go with Sch 40 1.5" mild.
Stein's build thread has the best pics I've found thus far
I <3 this thread
Also, now I am not so sure that Schedule 10 wouldn't be fine. Wall thickness is .109" vs .145 so plenty there. Weld Els go down to $4.95 for 1 1/2" long radius stainless els in schedule 10. As a matter of fact, I may have used schedule 10. Pretty sure I did.
You have to put one end in the vise to smash it down to oval it to match the ports in the head flange but it's no biggie.
You have to put one end in the vise to smash it down to oval it to match the ports in the head flange but it's no biggie.
Are you TIG welding? If not, go mild steel. It's easier to cut and it DGAF what filler you use. Prices are actually higher for mild steel over stainless but a couple of bucks would be less headaches cutting the els...
Schedule 40 will be more tolerant of shitty cutting and fitment as you can put more heat into the gap and the heavier wall will help bail you out.
Schedule 40 will be more tolerant of shitty cutting and fitment as you can put more heat into the gap and the heavier wall will help bail you out.
Stein's build thread has the best pics I've found thus far
I <3 this thread
Last edited by EO2K; 10-18-2012 at 05:49 PM.
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10-18-2012, 05:47 PM
#152
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1.5" matches perfectly to the exhaust port size, that is after you oval it out. Like I mentioned before, if I had known how big of a PITA it was going to be oval the pipes and do all of that part of the pipe fitment, I would have shelled out the extra money for the CNC oval to round port flange. I really need to update this thread too. I finally got my exhaust housing ported out and need to finish the manifold now.
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10-18-2012, 07:26 PM
#155
1.5" matches perfectly to the exhaust port size, that is after you oval it out. Like I mentioned before, if I had known how big of a PITA it was going to be oval the pipes and do all of that part of the pipe fitment, I would have shelled out the extra money for the CNC oval to round port flange. I really need to update this thread too. I finally got my exhaust housing ported out and need to finish the manifold now.
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10-18-2012, 10:04 PM
#156
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On another note, I finally finished my turbo hot side to my satisfaction, so the manifold building can commence. Hopefully this significantly helps spool.
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