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Old 02-19-2013, 09:35 PM   #1
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Default Someone please 'splain "bend radius" to me.

Like the title says.

I'm shopping for U bends and 90* bends.Did a quick google search, and all of the answers are ridiculously overcomplicated (or maybe I'm dense).

I want to basically have 6-7" of space between the inner tip of one leg to the inner tip of the other leg of the U. I need to know what bend radius will get me that.

Holler at me.
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Old 02-19-2013, 09:36 PM   #2
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Or, if someone has the BIG magnaflow (5x11x22 iirc) please post up which U bend you used.
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Old 02-19-2013, 09:38 PM   #3
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Using this chart:



Would I need a 3-3.5" bend radius to get me my 6-7 inches?
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Someone please 'splain "bend radius" to me.-300-pipe-bend-radius3.jpg  
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Old 02-19-2013, 09:56 PM   #4
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In your diagram, bend radius (also referred to as Center Line Radius) is R1. If you want to get R2, you subtract half the diameter.

To put 6" of space between a 3" 180* bend, you need a bend radius of 4.5", which is the standard 3" bend radius (the tightest possible is 3").
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Old 02-19-2013, 11:53 PM   #5
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Thanks Andrew. Exactly what I wanted to know.
+props
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Old 02-20-2013, 09:15 AM   #6
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You can fit the big boy magnaflow without a U. I've seen it on a 45, i just can't find the pics anymore.
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Old 02-20-2013, 10:10 AM   #7
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I'll test it out, if it really works without having to hack up anything at all, I'll do it. If it doesn't, or rubs/hits, or is weird looking, I'll just go traditional like you and y8s
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Old 02-20-2013, 10:17 AM   #8
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I would prefer it that way, not that it really matters, but after savington said he noticed a slight loss in spool-up...I have to assume it's the 90 into a 180 doing it.
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Old 02-21-2013, 08:00 PM   #9
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Very curious on fitting a 5x11x22 muffler at 45 degrees. Keep us posted.

Are you using the muffler with center inlet/outlet, or offset inlet/outlet?
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Old 02-21-2013, 10:04 PM   #10
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Pretty sure I saw him post a pic of it with center in/out in another thread
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Old 02-21-2013, 10:41 PM   #11
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The center in/offset out is the easiest to fit. Offset/offset has to sit further forward and ends up being harder to install.
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Old 02-21-2013, 11:35 PM   #12
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Yep I agree.

Want me to find the radius of the 180* to fit it for you?

Dann
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Old 02-21-2013, 11:41 PM   #13
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Sure, if you could.

The one you posted in the other thread is a 5x11x22 right/
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Old 02-22-2013, 07:52 AM   #14
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Yeh it is. I'll get measurements tomorrow for you.

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Old 02-22-2013, 09:18 PM   #15
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247mm Centre to Centre of the parallel pipes.

170mm space between the parallel pipes.

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Old 02-22-2013, 09:20 PM   #16
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so 6.7 inches.
got it.

thanks

so I need something like 5-5.5 bend radius
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Old 02-23-2013, 04:37 AM   #17
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If you are using 3" you will need half of 170mm.


Which is 4.5" bend radius.

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