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Modification advise please

PostPosted: Sun Jan 01, 2012 10:11 pm
by jeffas4966
Hi All,
My MY08 TBSTI (auto wagon) is now out of warranty so it will soon be time for mods.
I will be upgrading to
1.TD05-20G
2. Fuel pump
3. TBE
My queries are
1. Do I need a twin scroll turbo to replace the existing or is the existing a single scroll. I suspect the 2.5s are single?
2. What do you guys recommend eg Walbro 255
3. I am thinking TCP, but overall I am concerned about noise, any thoughts


Thanks in advance

Re: Modification advise please

PostPosted: Sun Jan 01, 2012 10:53 pm
by Stu
Hey Jeff,
The 2008 models should all be single scroll, so no need to go the twin scroll (jack-of-all-trades master of none :? sorry guys)

I'd definitely go for a fuel pump upgrade when upsizing the turbo. I've personally just bought an Aeromotive 11142 pump for my future plans :wink: some guys here might think it's a little much, but I'd rather have slightly warmer fuel than not enough fuel at the injectors. I'd also heard the Walbro might be noisy and a little tricky to install, but completely open to correction here.... just reading too many forums

Exhausts are completely personal preference, I'd drive around with 4" pipe out the front guard if I could get away with it. Check the vids on the exhaust forum, or try to find someone with a liberty or wrx with the TCP.

Re: Modification advise please

PostPosted: Mon Jan 02, 2012 12:39 pm
by Jaz
I have a TCP exhaust, I beleive I was the first, as it's my car in the vid online.

Inside the car the TCP is really good, sounds great, and it's certainly not overpowering. I don't think you'd consider it too loud. It's loud enough that you can't sneak home though if you're in the dog house...
It, an intake and tune should put a nice smile on your face. Adding the turbo should get you a better result than I did.

Re: Modification advise please

PostPosted: Wed Jan 04, 2012 7:57 pm
by rooby
I have had the TCP exhaust for a few months too and I really like it. It has a nice noise but isn't too loud.
It has a little bit of drone at freeway speeds but not much at all, the only time it is really noticeable is when you have no music on and are talking to a passenger.
Cruising at lower rpm is pretty damn quiet.
That is just my opinion though, loud is different for everyone.

Re: Modification advise please

PostPosted: Wed Jan 04, 2012 10:05 pm
by ndlibgt
Totally agree with Rueben, everyones definition of loud will differ. Although a tad louder than what i was hoping for i'm am happy with how it sounds. Here's a link to my exhaust clip, bear in mind this is a 2.0L. Also it's not a full TCP TBE as Ionly have TCP muffs with a maganflow in the factory centre and a Phat dump. (Might get custom centre done in the near future).

viewtopic.php?f=55&t=2382&start=150#p199448

Re: Modification advise please

PostPosted: Fri Jan 06, 2012 10:01 pm
by yipming
Interested to know what your thoughts are on the gearbox.
How would you go about strengthening the gearbox to handle the extra torque and power?
Or are you comfortable with the 5eat?

Re: Modification advise please

PostPosted: Fri Jan 06, 2012 11:01 pm
by dr20t
The stock auto will be fine up to 200 kw at the wheels.

Anything beyond that will need a shift kit and or upgraded stall convertor

I'd stick with a phat dump and tcp exh thereafter

20g will be too big for an auto 2.5 unless you have someone with exceptional avcs tuning knowledge tune it so you can get some significant cam timing advance in low to mid range revs.

Otherwise I'd stick with an 18g especially if running restrictive intake.

Good luck with the build

Mick

Re: Modification advise please

PostPosted: Fri Jan 06, 2012 11:22 pm
by <GB>
How much power would u want to make, I would def go the fuel pump exhaust dump pipe first

Re: Modification advise please

PostPosted: Fri Jan 06, 2012 11:38 pm
by dr20t
<GB> wrote:How much power would u want to make, I would def go the fuel pump exhaust dump pipe first


In reverse order ie dump pipe exhaust fuel pump then tune

Modification advise please

PostPosted: Sat Jan 07, 2012 6:40 am
by Gambit
Stu wrote:I've personally just bought an Aeromotive 11142

stu you will find the aero will need just the slightest mod to fit up.

For everyone else new drop in fuel pump from deatschwerks dw65c, worth checking out.

http://legacygt.com/forums/showthread.p ... ?p=3644945

Re: Modification advise please

PostPosted: Sat Jan 07, 2012 10:25 pm
by Stu
Gambit wrote:
Stu wrote:I've personally just bought an Aeromotive 11142

stu you will find the aero will need just the slightest mod to fit up.

For everyone else new drop in fuel pump from deatschwerks dw65c, worth checking out.

http://legacygt.com/forums/showthread.p ... ?p=3644945


Yep fitted the Aeromotive pump the other day, took a few sessions of grinding/cleaning/testing on the pump caddy where the plastic sticks out and also couldn't use the OEM pickup filter since it was too long to fit the bucket back on. Luckily Aeromotive supply a shorter pickup filter which bends a little to fit. Smelt like Ultimate98 for a few days afterwards :lol: (mental note: try to replace pump next time with near empty tank)

So yes a drop in fit from Deatschwerks would be the go with less to worry about!

Re: Modification advise please

PostPosted: Sun Jan 08, 2012 9:59 pm
by jeffas4966
Thanks Guys,
I have already got a price from TCP.

The power target for me is 200kwsatws which I thought the auto box would do easily.

My other issue is I don't want to run really high boost 16-17psi max. Do the 20g's work OK at that boost level?

Rgds

jeff

Re: Modification advise please

PostPosted: Sun Jan 08, 2012 10:38 pm
by dr20t
20g won't come into it's efficiency until 18psi to 20psi. You must remember that the 20g is a 45lb/m compressor, so it will deliver a pretty hard punch, but the Subaru auto stall convertor does not provide full lock up until 3000rpm or so in the lower gears, and about 2500 to 2700 in fourth depending on load.

What does this mean - essentially it will be harder for you to load up the engine sufficient enough to generate the required exhaust gas pressure and density to make the turbo come on. At those boost levels you are better off going a diffrrnt type of turbo

Irrespective of what anyone tells you, there is no direct bolt on turbo for the twin scroll liberty engine. Therefore in any event of an upgrade you will need to modify your uppipe, and if you're doing so you may as well go for a properly sized turbo. My recommendation is a gt2860rs disco potato, or a Borg Warner billet wheel twin entry s240sx. Look up the specs you will shit and no mhi based turbo will come close to spool up characteristics and flow of the latter especially.

Good luck

Re: Modification advise please

PostPosted: Sun Jan 08, 2012 10:57 pm
by dr20t
Edit - my apologies I thought you had a two litre

Your 2.5 is a single scroll which makes it a little easier.

In any event there are various bolt on upgrades including the ones Mentioned above to suit your application.

The beauty of these and why I prefer them over the mhi ones are the availability of sold compressor maps which you can use to decide on the correct turbo

Mick

Re: Modification advise please

PostPosted: Sun Jan 08, 2012 11:57 pm
by jeffas4966
Cheers Mick,
So do you feel an 18g would serve me better?

Cheers

Jeff