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Old 02-08-2009, 11:08 AM   #21
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Default internal waste gate con

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Old 02-08-2009, 11:08 AM   #22
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Old 02-08-2009, 02:21 PM   #23
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Well let me be one to say that i am glad i am going external for this build.
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Old 02-08-2009, 02:43 PM   #24
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Quote:
Originally Posted by SolarYellow510 View Post
Build a 2.5" downpipe with a proper bellmouth before worrying about what kind of wastegate you have.
Yes, I realize my downpipe is not optimum, that's why this thread. If I decide to retain the internal wastegate, I would rather do a divorced muffled dump tube using one of these:

SuperTrapp 344-2005 - SuperTrapp Disc-Only Mufflers - summitracing.com

than a bellmouth. That would be the easiest solution at this point, rather than having to deal with mocking up and welding a new 2.5" downpipe.


Quote:
Originally Posted by 18psi View Post
External gate controls boost way more presisely. Dont know about power gains from it over an internal, but I wouldnt think them to be that big. They cost money and a bit more work to plumb in (assuming you dont already have a ewg ready setup)
Internal is OK but definitely not as precise or good as external. I chose to go internal on my setup, just for the simplicity of having it on the turbo and what not. I know, not a really good reason but w/e.
Define precise. If its no better than what I can achieve with EBC and the existing internal setup, then its too much hassle really.

Quote:
Originally Posted by 18psi View Post
WRX's using same turbo gain a SIGNIFICANT amount of power from a bellmouth downpipe compared to the one you are using, especially up top where you say you can use a bit more.
Do you have any data on what typical gains are on a stock TD04 using a bellmouth? dyno plots, datalogs etc or even just a number would be helpful.
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Old 02-08-2009, 04:18 PM   #25
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Quote:
Originally Posted by The_Pipefather View Post
Yes, I realize my downpipe is not optimum, that's why this thread. If I decide to retain the internal wastegate, I would rather do a divorced muffled dump tube using one of these:

SuperTrapp 344-2005 - SuperTrapp Disc-Only Mufflers - summitracing.com

than a bellmouth. That would be the easiest solution at this point, rather than having to deal with mocking up and welding a new 2.5" downpipe.




Define precise. If its no better than what I can achieve with EBC and the existing internal setup, then its too much hassle really.



Do you have any data on what typical gains are on a stock TD04 using a bellmouth? dyno plots, datalogs etc or even just a number would be helpful.
External gates can react quicker to changes in boost than an internal gate. Less likely to overshoot when boost comes on for example. They also hold more solidly when in boost. Look at my boost curve with a MBC and external gate. Note, I don't have it configured for dual port yet. Once I do, spool should improve further.

IMO:

Dual port EWG + MBC is better than internal WG plus EBC. Both would spool about the same, but mine will not overshoot, or require tuning, or change when temps drop, etc.

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Old 02-08-2009, 04:25 PM   #26
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i can make mine look really flat too....

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Old 02-09-2009, 03:18 AM   #27
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Quote:
Originally Posted by The_Pipefather View Post
Yes, I realize my downpipe is not optimum, that's why this thread.
Define precise. If its no better than what I can achieve with EBC and the existing internal setup, then its too much hassle really.
Do you have any data on what typical gains are on a stock TD04 using a bellmouth? dyno plots, datalogs etc or even just a number would be helpful.
Pat pretty much covered the other question, but here is my take on the dp:
bellmouth downpipe with 3" exhaust and tuning usually nets a good 40whp on wrx's that I have seen. May be a bit more may be a bit less. The response and torque curve jumps significantly, and while the td04 still runs out of breath up top (on a subaru) it is still way better than with that pos plate with small pipe that they call a downpipe that it comes with stock.

I would just keep the iwg if I were you. You are already done with your build and have it set up this way I'd leave it. But thats just me. If you were starting on a build right now I'd recommend ewg though.
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Old 02-09-2009, 08:37 AM   #28
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This would simplify my planned build for an external gate immensely but goddamn is that a rubber mount on the end? How the hell will it hold up to heat?

I need to look for some reviews.

Edit: Seems to be noisy for DSM guys. Would cost a fair bit more than just rerouting back into the DP for me anyhow.

Last edited by DragonsMaw; 02-09-2009 at 09:01 AM.
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Old 02-09-2009, 09:06 AM   #29
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Old 02-09-2009, 11:41 AM   #30
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Bad, good, better, best

Stole this from the downpipe FAQ over at NASIOC.

Go all the way to the right.

And hook it back in. If you buy one big 1 3/4 j-bend from Summit, you'll have more than enough curves to do that. I've driven cars that dump separately, and you can't get on boost without everyone in a mile radius knowing about it.
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Old 02-12-2009, 05:56 PM   #31
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Quote:
Originally Posted by NA6C-Guy View Post
Can one make an internally wastegated turbo into external as easily as welding up the internal, and going with an external mount manifold?
That's what I'm planning to do... Pics!
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External wastegate - Pros and Cons-incon-gtbb3701-01.jpg   External wastegate - Pros and Cons-incon-gtbb37-turbo01-01.jpg  
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