PDA

View Full Version : Bottom mount with external wastegate? GT2871R SR20DET


Jersthecool
06-17-2014, 09:34 PM
I've currently got a bottom mounted megan manifold with a GT2871R on an internal wastegate which is causing me grief when wanting to run more boost and opening early causing more lag then I'd like. So I decided I'd really like to go with an external setup. Top mount is an option as they do make T2 manifolds but I don't want to spend the money with all the other things involved to change it, manifold, new piping, new turbo outlet pipe, new oil lines etc. So I'm thinking to stay bottom mount would be a better option however I'm having a hard time finding a bottom mount tubular manifold with a wastegate flange, the only thing I seem to be able to find is the stock manifolds with a flange welded on but I'd prefer a tubular style setup. Does anyone know where I'd be able to find one?


EDIT: Pretty much only been able to find one and it's out of new Zealand
http://www.hybridperformance.co.nz/hp/product.php?id_product=84

Seraphim38
06-17-2014, 10:22 PM
just switch to the T25-EWG-44 turbine housing from ATP. It replaces the back half of the turbo and enables you to mount a Tial MVR on the side of your turbo. Then you can keep your same exhaust manifold. I had one on my car and it didn't spool up as fast as the prior .64AR housing, but it did perform very reliably as far as boost control. It is advertised as a .73AR I think. And yes there is at least one tubular bottom mount manifold that offers external wastegate piping...I think it started with an N but I don't remember the brand. Very rare, but obtainable. Anyway, the most accessible and affordable option:

http://www.atpturbo.com/mm5/merchant.mvc?Screen=PROD&Product_Code=ATP-HSG-043&Category_Code=HSG

http://www.atpturbo.com/mm5/graphics/00000001/Catalog%20Images/Turbochargers/ATP-HSG-043_450-1.jpg

search for Huffandpuff's posts in the GT2871r thread. He posts several pics of his setup. There's pics of my setup too (I have moved on to bigger and better things since)

angel mkiv
06-17-2014, 11:27 PM
Go with the doc racing exhaust manifold with the external wastegate option..

http://www.docrace.com/index.php?main_page=product_info&cPath=36_52&products_id=89&zenid=bf92c62f19d9f460d12c91b2ef5e82fd

huffandpuff00
06-18-2014, 02:02 AM
EDIT: Pretty much only been able to find one and it's out of new Zealand
http://www.hybridperformance.co.nz/hp/product.php?id_product=84
^^^ that looks like a cheap manifold. either go with a doc manifold and have them add an EWG flange, get an exhaust housing and add a EWG flange to it or have codyace make you a stock manifold w/ EWG flange. best 3 options imo....

option 2: http://zilvia.net/f/showthread.php?t=564456

Seraphim38
06-18-2014, 08:10 AM
I thought you might still have it for aale but wasn't sure ;)

Sent from my SGH-T999 using Tapatalk

KoukiMonsta
06-18-2014, 12:01 PM
Get a Cody ace manifold. End of story

Seraphim38
06-18-2014, 12:04 PM
A codyace manifold does not solve the turbine housing internal gate issue.

Sent from my SGH-T999 using Tapatalk

corby_baby
06-18-2014, 12:28 PM
A codyace manifold does not solve the turbine housing internal gate issue.

Sent from my SGH-T999 using Tapatalk

but welding the internal gate closed will.

Seraphim38
06-18-2014, 12:32 PM
Of course, but that is why the t25ewg44 is a simple solution. Anyway...

Sent from my SGH-T999 using Tapatalk

e1_griego
06-18-2014, 01:10 PM
Didn't you complain that the .72 a/r was too laggy?

My next step will be vband bottom mount w/ EWG flange, but until then Codyace mani with wg welded shut is working well.

RalliartRsX
06-18-2014, 01:33 PM
Lots of options, opinions and answers being thrown around without the actual culprit in question being addressed: the internal gate and why it's opening so early.............. (or as pointed out by another individual, running anything bigger than a 0.64 T2 turbine housing and then complaining of "lag"..................)

The easiest and cheapest option would simply be to run a better internal gate than what is on there now..........but then that leads to the question: why are you asking these questions without evening giving us pertinent information on the internal gate itself?? Is it a knock off?? Is it a genuine HKS?? What is it??

If your gate is opening too early that to me, immediately points to a diaprahm/vacuum port (internal) or spring/vacuum port (EWG) issue. If that is not the issue, then you need to delve deeper.

huffandpuff00
06-18-2014, 07:50 PM
Didn't you complain that the .72 a/r was too laggy?

My next step will be vband bottom mount w/ EWG flange, but until then Codyace mani with wg welded shut is working well.

defiantly stay away from the .72ar housing! slooooow spool :( The one i have for sale is NOT the T25-EWG-44.

as for your new setup alex, get at DOC and they will hook it up for local guys and cash transactions :)...you'll probably have a new setup on your car before mine gets running, school loans are no bueno

e1_griego
06-18-2014, 09:35 PM
Nah, no reason to switch just yet. When I blow the t2 gasket again I'll think about it. I just bought a 2863 for my other s13 so I wanna get that going first.

az_240
06-18-2014, 09:45 PM
Is there a downside to running the PBM cobra downpipe specifically made for internal wastegate (divorced) with the wg welded shut and EWG?

I have the PBM downpipe sitting around but want to go with the codyace mani....

I'm not aware of any downpipes that are similar without the divorced elbow.

e1_griego
06-19-2014, 12:55 AM
^Been running that setup for a couple years now. No downside that I can find.

huffandpuff00
06-19-2014, 06:40 PM
only 2 things i could think of would be the smaller size creating back pressure or the divider creating turbulence.

Jersthecool
06-19-2014, 07:54 PM
Well huge thanks for that link to that housing, that's probably gonna be the way I'm going. You say it's laggy which it might be compared to the .64 but honestly right now I'm running the .86 and debated switching to the .64 and now this is a perfect median between the two so I'm even happier about that.

RalliartRsX for you wondering, I'm not too worried about it opening early it's not like it's opening super early I just know how internals start to open as boost is building so with an external I may get a tiny bit less lag maybe even nothing noticeable. The biggest thing I'm wanting to do is run more boost and I'm just running the stock wastegate no knockoffs and it won't hold more than 15 psi, even 15psi just drops right off down to wastegate pressure 12psi. I've considered the hks actuator but I would much rather run an external so it won't open early and as well the added sound.

az_240
06-19-2014, 08:10 PM
only 2 things i could think of would be the smaller size creating back pressure or the divider creating turbulence.

This is what I'm afraid of... I'm thinking of just selling it and doing something custom since I kinda want the ewg plumbed into the exhaust anyway. Not a fan of open dump.

zurud
06-22-2014, 08:51 PM
Get electric boost controller. My stock 2871r come with 15psi wastegate. I can hold 25 psi to 8k

Livinstrong
06-23-2014, 11:05 AM
I agree, an electronic boost controller should solve this problem. When you switch to the other housing, it wouldn't create as smooth of power band as a electronic boost controller would.

RalliartRsX
06-23-2014, 11:25 AM
I agree, an electronic boost controller should solve this problem. When you switch to the other housing, it wouldn't create as smooth of power band as a electronic boost controller would.

Huh?!?! You do know a smaller housing will probably spool better and have a much wider/larger area under the curve correct??

:bash:

Livinstrong
06-24-2014, 01:20 PM
Huh?!?! You do know a smaller housing will probably spool better and have a much wider/larger area under the curve correct??

:bash:
Yes, but an electronic boost controller will make sure that the actuator doesn't prematurely open and cause a longer spool up time. Instead of slightly opening at say 5psi, it will keep the internal waste gate completely closed until maximum boost is achieved and only then will it allow excess gas to escape to the exhaust system.