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-   -   is there a direct bolt in twin scroll turbo that we can upgrade to? (http://legacygt.com/forums/showthread.php?t=6911)

mycotopian 01-11-2005 12:22 PM

is there a direct bolt in twin scroll turbo that we can upgrade to?
 
is there a direct bolt in twin scroll turbo that we can upgrade to or do we have to do a full turbo, intercooler,IM and piping swap?

thesmokingman 01-11-2005 12:29 PM

Twinscroll by definition, requires major changes. All the needed parts will technically bolt-on... ;)

mycotopian 01-11-2005 12:41 PM

How many miles should I put on the stock setup before I ad the ap and amaybe do the twin scroll setup?

Boostjunkie 01-11-2005 12:42 PM

Second that, although it seems that the changes can be fairly simple as long as you get the right parts. You will need the JDM twin scroll manifold, turbo and downpipe of course. If you get the JDM Legacy turbo you should be able to bolt-up to the stock intercooler. If you use the JDM WRX twinscroll you will need it's intercooler and intake manifold as well. Look at ShaggyGT's post about his setup. It's all pretty much bolt-up, but there are a fair number of parts involved.

Boostjunkie 01-11-2005 12:45 PM

Quote:

Originally Posted by mycotopian
How many miles should I put on the stock setup before I ad the ap and amaybe do the twin scroll setup?

At least break-in the car for 1000 miles, before you start modding. Start with the usual USDM bolt-on stuff if you aren't sure about how much you want to push. You might be satisfied and stop there. If you aren't then consider the twin-scroll. By itself the twin-scroll doesn't make a ton more power, just allows you to have better spool-up while still increasing power potential. You can get great spool-up on an uprated standard turbo if you select your parts carefully and do some port work on the manifolds, head and turbo.

offthacliff 01-11-2005 09:55 PM

Heres an email reply I just got regarding the twin scroll set up............

>>>>>>>>>>Cliff,

Cost to you on the '05 GT AVO Catback is $1388+ Ship.

That looks great! I have talked to him before. Nice setup. My only concern
is the JDM stuff is for a 2.0L engine and may be a bit undersized for the
USDM models.

The factory JDM setup uses a different connection to the intercooler than
the USDM model. You could retain the original manifold, but you will have to
use a JDM TMIC.

AVO will have a replacement turbo for the GT in a few months! Perrin has a
TMIC available soon!

Thank you for asking,

Sean Sexton
www.RalliTEK.com / www.Rallitek.net





-----Original Message-----
From: Cliff2201@cs.com [mailto:Cliff2201@cs.com]
Sent: Thursday, January 06, 2005 10:55 AM
To: Sean@RalliTEK.com
Subject: 05 LGT


Sean, what is your price on the AVO CBE for the 05 LGT?

Also,
A guy in our fourm, modded his 05 LGT with some STI parts... Check it out:
http://www.legacygt.com/forums/showt...8&page=1&pp=10

He used.... Version 8 STi Spec RA Twinscroll turbo setup, which includes the
equal length twinscroll exhaust manifold, twinscroll uppipe, and VF37
Twinscroll turbo.

I am more interested in the factory JDM LEgacy twin scroll set up, as i
believe i could retain mt Stock TMIC and Intake manifold...
BASICLY THE VF38 TURBO, JDM EQUAL LENGTH EX MANIFOLD, JDM TWIN SCROLL UP
PIPE, JDM DOWN PIPE, AND GASKETS.

LET ME KNOW WHAT YOU FIND... THE LGT IS A NEW HUGE MARKET NOW!

Thanks-
CLIFF

offthacliff 01-11-2005 10:14 PM

[QUOTE]At least break-in the car for 1000 miles, before you start modding. Start with the usual USDM bolt-on stuff if you aren't sure about how much you want to push. You might be satisfied and stop there. If you aren't then consider the twin-scroll. By itself the twin-scroll doesn't make a ton more power, just allows you to have better spool-up while still increasing power potential. You can get great spool-up on an uprated standard turbo if you select your parts carefully and do some port work on the manifolds, head and turbo.[QUOTE]

I don't know if I agree...
First, If you are planning a twin spool set up, why spend money on aftermarket UP/DP that wont work with the Twinspool?
Why not add the Twin Spool set up, then Modd to aftermarket Twin spool UP/DP and Equal length Manifold!
For me, IM trying to decide on wich path to choose...
Either go with the AP, and aftermarket UP/DP.
Or A twin spool set up (Turbo, UP/DP, bolth Manifolds, TMIC) and EcuTek with a custom tune.
One thing is for sure... IM not doing them bolth.
And port work on Everything is more work than bolting on the twin scroll set up.

mycotopian 01-11-2005 10:43 PM

I am definetly goinf to be looking at going with the twin scroll setup so I guess I'll put 1k on the drivetrain and then take a look at how much everybody has jacked up prices on the VF38.

Boostjunkie 01-11-2005 11:06 PM

It's actually the VF37(plain bearing) and VF36(ball bearing) that are the twin scroll turbos. The reason I said do the other stuff first is that it is still cheaper and much easier than importing and installing a twin scroll setup. Most will be satisfied with that and call it a day.

What you have to be realistic about is what a twin scroll setup will get you. For less money a larger standard turbine turbo bolted up and tuned will offer more peak hp potential. What you get with the twin scroll is about the same power potential as a stock STi VF39, with faster spool-up. If you want more peak power, you are barking up the wrong tree.

Regarding spending on US spec upgrades first, unless you import an aftermarket JDM downpipe you will be fabbing a downpipe anyways. Some who have done the twin scroll setup have simply cut the flange off their USDM aftermarket downpipes and welded on the twin scroll downpipe flange. The uppipe would be useless, but the resale market is strong for them. Heck I just bought an STi uppipe from a guy who did a twin scroll swap on his STi. So really you won't be spending the money twice. Trust me, I hate that.

Unless you've driven a twin scroll car and have to have it, I'd just pursue the cheaper proven USDM mods. Really if you think of it, swapping to stock JDM parts is the epitome of spending money twice. You paid for the car with a stock manifold, turbo, TMIC etc.. now you are spending money again for a stock manifold, turbo, TMIC etc...

BoxerGT2.5 01-11-2005 11:14 PM

Quote:

Originally Posted by Boostjunkie
It's actually the VF37(plain bearing) and VF36(ball bearing) that are the twin scroll turbos. The reason I said do the other stuff first is that it is still cheaper and much easier than importing and installing a twin scroll setup. Most will be satisfied with that and call it a day.

What you have to be realistic about is what a twin scroll setup will get you. For less money a larger standard turbine turbo bolted up and tuned will offer more peak hp potential. What you get with the twin scroll is about the same power potential as a stock STi VF39, with faster spool-up. If you want more peak power, you are barking up the wrong tree.

Regarding spending on US spec upgrades first, unless you import an aftermarket JDM downpipe you will be fabbing a downpipe anyways. Some who have done the twin scroll setup have simply cut the flange off their USDM aftermarket downpipes and welded on the twin scroll downpipe flange. The uppipe would be useless, but the resale market is strong for them. Heck I just bought an STi uppipe from a guy who did a twin scroll swap on his STi. So really you won't be spending the money twice. Trust me, I hate that.

Unless you've driven a twin scroll car and have to have it, I'd just pursue the cheaper proven USDM mods. Really if you think of it, swapping to stock JDM parts is the epitome of spending money twice. You paid for the car with a stock manifold, turbo, TMIC etc.. now you are spending money again for a stock manifold, turbo, TMIC etc...

To add to what Boost said.....

Simply bolting on a twin scroll set up with a USDM ECU will probably hinder the cars ability, if not, make it run worse. So proper ECU tuning like ECUtek and vishnu would probably be something you'd be doing right away. Again, more coin out of your pocket. Twin scroll/equal length systems require different
A/F ratios and timing (just to start off). Yes....they are easy to tune for, but adding a twin scroll set up is not just simply bolt on. An intake is bolt on....this will take some thought.

thesmokingman 01-11-2005 11:22 PM

There is a lot of conjecture here...

BoxerGT2.5 01-11-2005 11:23 PM

Quote:

Originally Posted by thesmokingman
There is a lot of conjecture here...


Actually....it's already been done by a member on the board. :D

Boostjunkie 01-11-2005 11:37 PM

And many others on Nasioc

thesmokingman 01-12-2005 12:09 AM

Quote:

Originally Posted by BoxerGT2.5
Actually....it's already been done by a member on the board. :D

Actually, the fastest Subaru uses twinscroll and a 2 liter. Actually, the fastest Subaru running this twinscroll is the only STi to break the sub 8 minute lap at the 'Ring.

Lotsa regurgitation here. Not much actual experience.

Boostjunkie 01-12-2005 12:48 AM

Look buddy. Welcome to internet forums. Not everyone who posts has first hand knowledge of what they are talking about. Did you build and/or drive that sub 8 min lap STi... didn't think so. What we are all doing is sharing what we know, or have heard and feel is creditable. Sometimes we are wrong, sometimes not.

BTW, is the STi in question using a VF36 or VF37, or is it some other turbo that happens to be a twin scroll. BTW, when you say fastest that is in one arena. Is that same car the fastest drag Subaru? Probably not.

I'm sure there are a good number of upgrade turbo available in a twin scroll configuration. Of course there could be a car out there that runs like a bat out of hell with such a turbo.

What I was addressing was the original posters desire to run a twin scroll, without explicitly mentioning his goals. If he is into drag racing, he might be better served with a HUGE turbo to bolt-up to the stock plumbing. If he wants a turbo with fast spool-up and can settle for around 300 whp, then a twin scroll would be a fine option. All I'm saying is that it's not a panacea or the best answer to every question.


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