So I want a 3 Inch Downpipe... where do i go?
#5
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Are you using the GReddy manifold? The largest so far for that is supposed to be the BEGI downpipe. It's real tight back there against the firewall. If you have a custom manifold then you may have to go to a fab shop to do it. I had a 3"DP on my old setup (custom manifold too) as do other people, it's definitely possible to fit one in there.
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I'd wait to see what BEGi comes up with. Even with a 2.5" to 2.75" the divorsed wastegate setup should prove to be better than a sraight 2.5" to the cat. Maybe you can work with Corky to make the bottom half step up to 3".
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I have no real numbers on this but Jay Kavanaugh (miata.net / R&D @ Garrett) says a downpipe matching the exducer then with a divergent angle (I think 11 or was it 17°?) exiting the turbo is the ideal situaion. if you can somehow fit that in your engine bay, i think you'll get most of the benefit of the large exhaust....
#12
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Like this?
http://russmarshall.com/v/cars/cmc7/...10856.JPG.html
I had to modify the engine bay slightly ...![](https://www.miataturbo.net/images/smilies/smile.gif)
The cone is from Burns Stainless and it extends into the housing to block the wastegate.
If one could find combined cone and bend this could be done in a Miata.
hrk
http://russmarshall.com/v/cars/cmc7/...10856.JPG.html
I had to modify the engine bay slightly ...
![](https://www.miataturbo.net/images/smilies/smile.gif)
The cone is from Burns Stainless and it extends into the housing to block the wastegate.
If one could find combined cone and bend this could be done in a Miata.
hrk
#13
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Hahahahahaha!
I just noticed that on the main page of the forum the title of this post is truncated to "So I want a 3 Inch..."
With all the spam posts lately, only one thing immediately popped into my juvenile mind...![Jerkit](https://www.miataturbo.net/images/smilies/jerkit.gif)
Sorry, for the thread-hijack.
I just noticed that on the main page of the forum the title of this post is truncated to "So I want a 3 Inch..."
With all the spam posts lately, only one thing immediately popped into my juvenile mind...
![Jerkit](https://www.miataturbo.net/images/smilies/jerkit.gif)
Sorry, for the thread-hijack.
#14
2 Props,3 Dildos,& 1 Cat
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Like this?
http://russmarshall.com/v/cars/cmc7/...10856.JPG.html
I had to modify the engine bay slightly ...![](https://www.miataturbo.net/images/smilies/smile.gif)
The cone is from Burns Stainless and it extends into the housing to block the wastegate.
If one could find combined cone and bend this could be done in a Miata.
hrk
http://russmarshall.com/v/cars/cmc7/...10856.JPG.html
I had to modify the engine bay slightly ...
![](https://www.miataturbo.net/images/smilies/smile.gif)
The cone is from Burns Stainless and it extends into the housing to block the wastegate.
If one could find combined cone and bend this could be done in a Miata.
hrk
reality unfortunately dictates you can either bend first and then flare OR use a stubby flare and then bend. I'm torn but I think I'll be turning first and then flaring.
#15
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Like this?
http://russmarshall.com/v/cars/cmc7/...10856.JPG.html
I had to modify the engine bay slightly ...![](https://www.miataturbo.net/images/smilies/smile.gif)
hrk
http://russmarshall.com/v/cars/cmc7/...10856.JPG.html
I had to modify the engine bay slightly ...
![](https://www.miataturbo.net/images/smilies/smile.gif)
hrk
![Biggthumpup](https://www.miataturbo.net/images/smilies/biggthumpup.gif)
#16
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Contact Rob at www.Flipsidecustoms.com. He fit one on his old Greddy setup. You won't lose any low end. Just nice spool and power gains.
#17
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YOU DON'T NEED TO HAVE A FULLY SIK 3" DUMP PIPE. You have your hand on your sausage. 3" is overkill on a 2L engine, what do you have? ![Biggthumpup](https://www.miataturbo.net/images/smilies/biggthumpup.gif)
Much more important is the velocity of the exhaust gases. The faster the gas, the better the exhaust system and bigger DOES NOT = faster flow. You will have LESS power with a 3" all the way through than with a matched custom system of about 2.5"(depending on your power level and capacity of course)
Do some reading, then get a 2.5" dump pipe.
60AGS
![Biggthumpup](https://www.miataturbo.net/images/smilies/biggthumpup.gif)
Much more important is the velocity of the exhaust gases. The faster the gas, the better the exhaust system and bigger DOES NOT = faster flow. You will have LESS power with a 3" all the way through than with a matched custom system of about 2.5"(depending on your power level and capacity of course)
Do some reading, then get a 2.5" dump pipe.
60AGS