So I want a 3 Inch Downpipe... where do i go?
#42
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http://www.bellengineering.net/Pages...peupgrade.html
Read it. I am happy to stand corrected on several of your points. Dragsters are not road cars, don't use them to back you up cause they are so different they aren't comparable. And if they use 4", what makes you think that a pissy little 1.6 needs 3" :gay:
Like I said, I stand corrected on some things and have learned a lot in this thread, and also laughed at a lot of comments. Don't put me down because of **** you have read on forums. ********* like us post on forums, what makes what we say right? I'd trust Begi though, they research.
Read it. I am happy to stand corrected on several of your points. Dragsters are not road cars, don't use them to back you up cause they are so different they aren't comparable. And if they use 4", what makes you think that a pissy little 1.6 needs 3" :gay:
Like I said, I stand corrected on some things and have learned a lot in this thread, and also laughed at a lot of comments. Don't put me down because of **** you have read on forums. ********* like us post on forums, what makes what we say right? I'd trust Begi though, they research.
well, to be fair, the V8 had two four inch pipes. if it were a 5.0, then it's 4" for 2.5L I guess.
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but as far as corky's comments about exhaust diameter, i simply disagree. I just don't have the means to test myself and prove it one way or the other.
matt
#43
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Brian, yes I do, if possible/legal. We have to have cats and mufflers, so you have to make do. My original comment was "bigger is not necessarily better". I stand by that. I have Corky to back me up too.
y8s - You are openly disagreeing with Corky's findings? :gay: More fool you!
That V8 would be bigger than 5L I think. But if it was, that is 4" for 2.5L. 1.6/2.5 = .64. 4" x .64 = 2.56". So your own example says you are oversized... hehehe.
By the way guys, I'm not having a go or trying to **** anyone off, I'm trying to help the guy who asked the question, and maybe learn some stuff myself.
y8s - You are openly disagreeing with Corky's findings? :gay: More fool you!
That V8 would be bigger than 5L I think. But if it was, that is 4" for 2.5L. 1.6/2.5 = .64. 4" x .64 = 2.56". So your own example says you are oversized... hehehe.
By the way guys, I'm not having a go or trying to **** anyone off, I'm trying to help the guy who asked the question, and maybe learn some stuff myself.
#44
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Have a good one.
#45
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T25, again, you're going against the accepted knowledge here, so I'd ask you to prove to us why you wouldn't want the largest pressure differential across the turbine that you could possibly achieve. This is how a turbo spools, so explain to us why you wouldn't want that.
The larger the diameter post-turbine, the more easily a turbo will spool. If that isn't so, please tell us why.
The larger the diameter post-turbine, the more easily a turbo will spool. If that isn't so, please tell us why.
#47
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That's the thing, though, the math seems right...again, you want the largest pressure diff. across the turbine you can have. The way to do this is with a big exhaust.
Is there a point at which you won't see any more gains? Sure. But you will see no downside or lost performance from going that large, either.
Is there a point at which you won't see any more gains? Sure. But you will see no downside or lost performance from going that large, either.
#48
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people on the supra forums are going with 4-5 inch downpipes... if there was no point for them people wouldnt be doing it. I understand the supra is a 3 liter so ya 4-5 seems normal. All of those people are running huge single turbos BTW. Im a big supra guy so I visit there forums often. I have a feeling 2.5 inch will be too small for some reason.
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Let's say you didn't care about having a legal exhaust or just planned to use the car at race tracks or something. Theoretically, if you had a 'downpipe' that was 3" diameter that came off the turbo, went straight down and back for a foot (needs room for a o2 sensor) and then dumped straight out right by the transmission, you would get great gains over a full exhaust. Yes?
-Ryan
-Ryan
#55
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If someone has there heart set on a 3" downpipe - make the turbine outlet flange 2.25", and every 10" swage the tube size up 1/2".
Stephanie
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But wait, whats this?
http://forum.miata.net/vb/showpost.p...18&postcount=3
Oh look, the need for 3" downpipe? Horse's mouth. Enjoy
http://forum.miata.net/vb/showpost.p...18&postcount=3
Oh look, the need for 3" downpipe? Horse's mouth. Enjoy
#60
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But wait, whats this?
http://forum.miata.net/vb/showpost.p...18&postcount=3
Oh look, the need for 3" downpipe? Horse's mouth. Enjoy
http://forum.miata.net/vb/showpost.p...18&postcount=3
Oh look, the need for 3" downpipe? Horse's mouth. Enjoy