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header lenth

Old 09-26-2007, 09:14 PM
  #1  
bentley marshall
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Default header lenth

how long should my header be just as a starting point ????
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Old 09-27-2007, 06:11 AM
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w3bby
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Default RE: header lenth

[link=http://nimrifmodels.co.uk/setup.html]Base setup info[/link]
With the wrap to centre (wtc) I have heard you shove it in as far as it will go without the O-rings leaking!!! You should be looking for about 12,5" - 13,5" from the flange to the start of the convergent cone. If I remember correctly the Cooper comes in two types, one that will tune well on a wtc and one that won't....
Old 09-27-2007, 03:54 PM
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bentley marshall
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Default RE: header lenth

thanks ian yes this one is for wtc and deep v headers so should tune in ok thanks for the set u info

bentley
Old 09-27-2007, 04:09 PM
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Default RE: header lenth

IS right between 11.5 TO 12.5
12.5 WILL BE THE BEST [8D]
Old 09-27-2007, 04:25 PM
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Default RE: header lenth


ORIGINAL: bentley marshall

how long should my header be just as a starting point ????
whats up didnt you believe me lol .
Old 09-28-2007, 05:03 AM
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hosnoopy
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Default RE: header lenth

The chamber you have is a normal pipe the WTC chamber has a shorter front cone.

I run my WTC setup 10mm back from were the O rings leek giving a length of 15" from the outside of the port. This is on a self mod 26zen running a MW3 just drops of pipe in a sharp turn.......

Running a normal chamber on a WTC header will give you a 16" pipe length at the least.

Go as short as you can without letting the O rings leak were the bend has been formed..

Running smaller props would need shorter lengths gepending on your setup. Good luck
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Old 09-30-2007, 10:11 AM
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Earth Surfer
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Default RE: header lenth

I just picked up a new pipe (need for speed) that has a header adjustment like yours. I am not sure I like the overlap of the header tube going into the pipe. I think I am going cut the tube 1/4" at a time, and test each cut, to get the tuned length that works best for the set up I am running. I* will probably buy a second header tube, in case my final cut went a bit to far. I am not sure, but I suspect the tube sticking into the pipe might effect the return wave duration or strength, and will most likely effect gas flow, so I want the header section cut off just past the last o-ring.
Old 09-30-2007, 11:19 AM
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martno1fan
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Default RE: header lenth

surely cutting the header pipe is standard practice for any tuned pipe setup?.you trim a bit at a time till you find the right tuned length,you dont want lots of header pushed up inside the tuned pipe as it will restrict it.as far as i know you cut all headers to just after the last o ring so your idea is just standard practice not something new .
Old 09-30-2007, 01:38 PM
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hse32
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Default RE: header lenth

About water cool pipe
[link=http://slappy.org/~john/sspipe.htm]http://slappy.org/~john/sspipe.htm[/link]
Old 09-30-2007, 07:43 PM
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glennb2006
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Default RE: header lenth


ORIGINAL: martno1fan

surely cutting the header pipe is standard practice for any tuned pipe setup?.you trim a bit at a time till you find the right tuned length,you dont want lots of header pushed up inside the tuned pipe as it will restrict it.as far as i know you cut all headers to just after the last o ring so your idea is just standard practice not something new .

Correct......

Glenn
Old 09-30-2007, 08:09 PM
  #11  
bentley marshall
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Default RE: header lenth

so it looks like i have the wrong pipe for the header im going to order a 100 deg header and that will fix every thing

is the lenth still going to be around 13"??? with that header
Old 10-01-2007, 04:07 AM
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Default RE: header lenth

start at 13 1/2" or even 14" and work in 1/4" at a time that should get you where you need to be,good luck mate.
Old 10-01-2007, 02:24 PM
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bentley marshall
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Default RE: header lenth

thanks mate hope to get out some time this week

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