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Doug Thorley headers Good? Bad?

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Old Sep 14, 2010 | 04:46 PM
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Default Doug Thorley headers Good? Bad?

So what is the general concensus on these? I've heard mention of headers on other sites but now I can't remember if they were the DTs that they were complaining about.
I understand also that DT is out of them? If they are "decent" fitting headers is anyone interested in doing anothere group buy? (term decent used loosely b/c I realize no after market headers are easy to put on).
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Old Sep 14, 2010 | 05:04 PM
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fit awsome i have no leaks, only issue with them that almost everyone has is the header whistle.
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Old Sep 14, 2010 | 05:58 PM
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i would be interested if they would let us do a group buy again
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Old Sep 14, 2010 | 06:09 PM
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I thought the whistle can be eliminated with a new flex pipe....right??
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Old Sep 14, 2010 | 06:21 PM
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yea im pretty sure thats what everyone did but don't know what flex pipe they used?
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Old Sep 14, 2010 | 07:01 PM
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I still have the DT flex because I am lazy. I can live with the whistle for now but I must say the stock mani's flow really good. You will be very surprised when you look down the tubes and see how big they really are. The headers do look great and are tuned to scavange better than the stock mani's. If you do not decide to go turbo then get them but if you are thinking going turbo then don't do it. I am glad I purchased the headers but do not think I'd buy them if they were over 600.00. After seening the stock mani's I am not sure I would have bought them. I'd certainly go back and forth about it.

-Mike
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Old Sep 14, 2010 | 07:03 PM
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Headers and tune = I love the them
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Old Sep 14, 2010 | 07:09 PM
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Not worth it IMHO with the stock intake manifold. 1 7/8" primary tubes is a little extream. I had them and they fit perfect and sounded awsome at WOT. Only down fall was the header whistle (sounds more like a exhaust leak ). Stock manifolds are fine, just port the rear outlet to 3". Its only 2 1/2 stock.
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Old Sep 14, 2010 | 08:57 PM
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I can do it up again.
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Old Sep 14, 2010 | 09:03 PM
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i gotta save some money first but then im down
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Old Sep 14, 2010 | 09:21 PM
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I am in too if we can coordinate it properly. I just need some time to get the funds together.
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Old Sep 16, 2010 | 09:41 AM
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Anybody have a video of a ls4 with headers and a cat-back system?
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