US Headers & Exhausts NA

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Dupain

Re: US Headers & Exhausts NA

Postby Dupain » Sat Aug 23, 2014 8:48 am

hks_kansei wrote:What's the port and pipe diameter of each primary?


Pretty much the same.

Dupain

Re: US Headers & Exhausts NA

Postby Dupain » Sat Aug 23, 2014 8:54 am

Giving it a wash with detergent, rinse, then clean with methylated spirits, once installed rinse with a bottle of vodka on first start up.

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Re: US Headers & Exhausts NA

Postby Mr Morlock » Sat Aug 23, 2014 2:51 pm

The welding looks very average to me. The whole thing looks like a nightmare. If it's too cheap then that's what it will be. If it does not fit bad luck. Detergent meths vodka Yeah that will make the difference.

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US Headers & Exhausts NA

Postby gslender » Sat Aug 23, 2014 3:09 pm

I don't know, I think after enough Vodka I could be convinced it's worth putting on the car.... Maybe just for laughs, you know, just like how slammin looks cool and stuff. Stupid in terms of what it does to performance and handling, but some folks think it looks wicked. I just see stupid.
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Re: US Headers & Exhausts NA

Postby Regie » Sat Aug 23, 2014 3:57 pm

equal length runners aye?? :roll:
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Re: US Headers & Exhausts NA

Postby Dupain » Sat Aug 23, 2014 5:46 pm

gslender wrote:I don't know, I think after enough Vodka I could be convinced it's worth putting on the car.... Maybe just for laughs, you know, just like how slammin looks cool and stuff. Stupid in terms of what it does to performance and handling, but some folks think it looks wicked. I just see stupid.



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Re: US Headers & Exhausts NA

Postby StuwieP » Sat Aug 23, 2014 6:57 pm

external diameter appears to change between welds? or is that just the photo/my eyes?
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Re: US Headers & Exhausts NA

Postby markwid » Sat Aug 23, 2014 7:37 pm

Agreed. Looks like a dog's breakfast, those unequal length runners.

If this is "tuned", it is done badly. I can't think of a good reason to deviate from what is tried and tested design for equal lengths.

For example, Xforce 4-2-1 design below showing how curls are used to achieve equal lengths.
Image

Mr Morlock wrote:The welding looks very average to me. The whole thing looks like a nightmare. If it's too cheap then that's what it will be. If it does not fit bad luck. Detergent meths vodka Yeah that will make the difference.

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Re: US Headers & Exhausts NA

Postby hks_kansei » Sat Aug 23, 2014 8:35 pm

Dupain wrote:
hks_kansei wrote:What's the port and pipe diameter of each primary?


Pretty much the same.



So they aren't tuned then?

Dupain wrote:So you would expect the primary on cyl one to have a slightly smaller internal diameter to tune it to compensate for thevextra length.




I mean, I could see they weren't tuned right from page 1 of the thread, but even by your own unusual definition of tuned they aren't...
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Re: US Headers & Exhausts NA

Postby Odd » Sat Aug 23, 2014 9:23 pm

markwid wrote:Agreed. Looks like a dog's breakfast, those unequal length runners.

If this is "tuned", it is done badly. I can't think of a good reason to deviate from what is tried and tested design for equal lengths.

For example, Xforce 4-2-1 design below showing how curls are used to achieve equal lengths.
Image

Mr Morlock wrote:The welding looks very average to me. The whole thing looks like a nightmare. If it's too cheap then that's what it will be. If it does not fit bad luck. Detergent meths vodka Yeah that will make the difference.


That's a very nice set of extractors....if the work half as well as they look they'd be brilliant
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Re: US Headers & Exhausts NA

Postby sailaholic » Sat Aug 23, 2014 11:41 pm

Hard to tell in the photo but the welds looks pretty average particularly the first weld after the flange one cyc 2.

Seems excessively curly given short the primary is still.


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Re: US Headers & Exhausts NA

Postby zero00 » Sun Aug 24, 2014 11:01 am

hmmmm .. I'll take the potplant
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Dupain

Re: US Headers & Exhausts NA

Postby Dupain » Sun Aug 24, 2014 11:40 am

Have you thought about the firing sequence?

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Re: US Headers & Exhausts NA

Postby plohl » Sun Aug 24, 2014 11:55 am

Yes.

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Re: US Headers & Exhausts NA

Postby Black_Penguin » Sun Aug 24, 2014 12:03 pm

Wouldn't make a difference, the idea is to have the 'pulses' of exhaust gas enter the collector at equally separate times. The order that this happens in is unimportant.
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