Hey all (new to forum)

Just wondering a couple things done on a 2005JDM STI (version 9). The car is 2.0ltr and totally stock.

What I was thinking was getting an ecutek reflash done while adding a cosworth flat panel filter and a turbo back exhaust.

My question is this: Assuming the whole system from the turbo back is 3 inch is there going to be any real down side in power or performance from me keeping the stock STI muffler (I really like the stock look and the STI-ness of it lol)

Also would I be right in expecting around 300-320hp from these mods?



As a sub question for the future if I am wanting 380-400hp would my best bet be to add a litchfield LM400 billet twinscroll with a larger fuel pump and 650cc injectors?

Thanks for your advice

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Ignore the above info, its old now


Ok so I have gathered some info and I just wanted to run it past your guys


The car is a blob eye 2005 JDM sti with the twin scroll.

My aim is around 380-400hp with near factory spool.

This is what I have as needed

MD321H 400 billet twin scroll turbo
3 inch turbo back exhaust
Harvey smith turbo up pipe (cant find a place that sells them though, help?)
sard or ID 650cc injectors
HKS premium suction kit
Cosworth flat panel drop in filter
larger fuel pump
Samco silicon turbo inlet pipe (a red one cos that makes it go faster)
ECU remap

1.4-1.5bar boost.

Win?

 

Greetings

I'll let someone with twin scroll answer the main, but I would say dith the stock exhaust for something free flowing, yet quiet if that's what you want, ie a Miltek.

You have a reasonable choice in turbos. In a addition to the LM try SC42, MD321, Or even a VF43 will do 380bhp.

Rob

 

i think you may have misread my initial post as I said the whole rest of the exhaust would be an aftermarket exhaust but just keeping the mufler OEM

 

- Cobra and Hayward & Scott (both UK) do aftermarket OEM STi style s.s rear boxes with 3" centre-section flange - with the rolled-in tail. In 3", 3.5", 4" and 5" tailpipe diameters (they just don't have "STI" stamped on the side of the tailpipe).

I would defo change it. It would seem a shame for you to go 3" turbo-back, only for the potential of the OEM back box to be choking power and possibly cause too high EGTs... Esp. for when you decide to go for 380+ later on.

Because turbos 'actively' push the exhaust gases out at great speed, then the bigger the better when it comes to exhaust components AFTER the turbo i.e. minimising choking or back-up. Torque won't be an issue because, once again, of the 'active' way a turbo manages the exit of the exhaust gases.


- As for your 380+ turbo choice, firstly, being a JDM, it is a twin scroll, right? (The supp. mods you mention will be perfect BTW).

 

The stock rear box really chokes the performance of the rest of the freeflowing exhaust.
I got done some time ago for a too loud exhaust (Blitz Nur Spec) and had to show up at the police station with a legal silence.
I stuck the original muffler on, but the car was not very driveable at all.
It would not reach target boost, and felt very lethargic all around.
(This was on a 2 liter with a td04, so way down on your proposed power level)

I would get a Milltek or another open muffler with the same look to it, that way you are not choking the car.

 

Not misread buddy, just stating that the stock exhaust would pretty much undo all the good work of the other components by restricting the flow, therefore actually creating a bottle neck effect for the gases to escape. But then aeveryone else has clarified that above anyway.

As I said before there is quite a nice range of Twin Scroll Turbo's out there these days.

MD321H Billet Twin Scroll
http://lateralperformance.co.uk/prod...877ce836112afa

SC42 Billet Twin Scroll
http://www.scoobyclinic.com/products_turbo.htm

I can get my hands on a cheap VF49 too if any use to you? Only done some WRC testing, so almost brand new for £600.

Rob

 

ok thanks for the advice guys, really appreciate it. I think I will go for the TBE and just forget about the STI badge fetish lol, Also I t appreciate the offer on the turbo but I am no where near ready to go ahead at this stage

 

yup its twin scroll too btw

 

Has some new info now, please read first post again

 

Yep, bang on mods.

What make is the fuel pump BTW?

What's an HKS "suction kit"? (I know who HKS are lol).


You get the uppipe from, er, harvey - email him.

At around 380+ it's a good idea to change to tubular headers too, as the OEM ones can be touch and go with allowing the flow. Although not so sure if the OEM TS ones suffer that.

If you do decide to get the tubulars, I think harvey does 2-bolt GT Spec1 (and possibly Spec2?) tubular TS versions, with appropriate 2-bolt TS uppipe. If not then RCM do their own 3-bolt TS headers (pukka kit but expensive) - and I think harvey can supply a suitable 3-bolt TS uppipe to go with them (as his ones have been tested to work great, etc.).

As said, email harvey with a link to this post - and he'll advise as appropriate...

 

is the md321 a true twin scroll or is it twin entry?

 

Thought the MD321 - and MDX321 (Billet) - series were only 'conventional' SS!(?)


EDIT: Ah yes, I see your point - as he mentions his turbo is a 321 (I overlooked that point in my previous post). There must be a TS version of the 321 then (unless he hasn't got it in his possession yet; or simply didn't realise! ).

 

i rememebr a thread a while back where a claimed twins croll turbo turned out to be twin entry and not twin scroll, can;t remember what it was though so might be a totaly different one.

 

LM and MD using same exhaust housing on their Twin Scroll

To OP:Twin scroll up pipe and headers are good enough,you don't need to upgrade to anything,Shaun here running still OE headers and Up pipe and doesn't seem is restricted by headers or up pipe


Jura

 

LM?

 

Litchfield LM4xx

http://www.turbodynamics.co.uk/shop/...za-p-2781.html



Jura

 

ah twin entry, so not a true twin scroll then as i understand it.

 

so basically it all looks good?

this is the HKS suction kit

http://www.scoobyparts.com/acatalog/...-_NEW_AGE.html

the fuel pump is walbro

 

would there be any advantage in tuning ability or fuel economy in my fitting an electronic boost controller such as HKS EVC or fitting an aftermarket fuel pressure regulator?

Was something suggested by my local tuning shop

 

I would go everytime with RCM V7 big cone or GGR big cone,we are running this cone at 490bhp without the problem

About the aftermarket Boost controller,would say,you don't need,your ECU can have two different maps as two different boost maps,if you want boost controller would say,Apexi AVC-R is way to go,but still think you will be OK without the boost controller.

Aftermarket FPR(Fuel pressure regulator) is good,but what injectors you are running,for those above turbo would say 650cc should be enough


Jura

 

dont need a boost controller, ecu does it

 

Is the samco silicon turbo intake pipe unnecessary? some people say yes some no?

 

Not sure,but OE turbo inlet is quite restrictive

Just beware before cheap Silicone copies,they can collapse under heavy boost


Jura

 

Samco is 'tuned' better than OEM pipe (being smooth internally).

Just hope that it doesn't collapse under boost when mapping (some suffer this; even Samco ones!).

 

Good choice by OP

Samco and Perrin intake pipes are ones I have used in the past with no issues under boost, but that running no more than 1.6 bar.

I have a cheaper one on the car at the moment, and it seems to be providing adequate flow, and no issues with collapsing.

Cant comment on the Twin entry / Twin Scroll scenario, again I was only offering advice from my own personal investigation. I believe Einstein is using a LM series turbo with cracking results on a stock engine. Might be worth dropping him a PM.

Rob
Rob

 

On my MY05 JDM STi when I had the LM420, Milltek 3", Litchfield 650 injectors, 255 Walbro fuel pump with standard air intake and TMIC I was getting approx 395 hp.

When I added BRD trumpet and filter, and Hybrid FMIC I've now got approx 425 hp

 

just to check we are talking about the same thing (cos Im still learning)

When we say turbo intake pipe are we talking about this??

http://www.maperformance.com/samco-s...e-wrx-sti.html

 

Yes

But when looking on this webiste,Perrin looking like good buy too,here is used too with good success.

Those Agency power or AMR hard inlet pipe are good too,but on yours shouldn't be problem to fit,main problem people have with TGV on their cars,but on yours,you don't have TGV


Jura

 

the perrin site doesnt like a seperate JDM or USDM market pipe, are they the same?

also whats TGV and what is it for? why dont I have it lol?

 

SFS intake pipe works a treat on my car.

I've witnessed myself Samco pipes cave in. Not cool for the price they are.

Steve