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Premium Member
2004 Forester XT
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923 Posts
Discussion Starter #1
I have seen an example of someone doing it with a manual here. Maybe someone else has?

I hope that alot of other folks haven't posted this question before, but I don't see any indication that they have based upon my searches.

Anyways it looks like several WRX have done it on their 2.0...(I am guessing that they are a little lighter though)...but maybe the 2.5 and the 4.444 final drive ratio could offset that?

Here is a thread on sub 13 second timeslips for WRX that caught my attention:

< 13.000 registry for TD04 turbos ( quick list II ) [Archive] - NASIOC

Anyone know if this is possible on 93 octane? I am willing to try just about every trick in the book to achieve this goal, I am just wondering if I should forget about it because of the 4EAT.

Any thoughts?
Thanks!!
 

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2004 Subaru FXT MT
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1,853 Posts
HA! Anything is possible...BUT

Putting on a bigger turbo is just too easy to bother...

^^My two cents.

You have to iron out absolutely all of the details mechanically, and drive like a madman. It can and has been done, but slapping on a bigger turbo with minimal other mods is just much easier...
 

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99 UK S-turbo
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8,590 Posts
I would say its possible, but you'll need to spend a lot more time/effort/money and make bigger compromises than doing it with a bigger turbo.....

On the turbine side the passages are 'too small', the turbine housing will need a full porting job, including the often forgotten 'letterbox' between the scroll and turbine, you'll probably also reduce some back pressure if you get the turbine blades cut back slightly.

The compressor is really marginal for size, so a lot of effort will need putting into easing air into and out (from Airbox to manifold) will help, the intercooler at high boost/flow is robbing circa 0.1bar of manifold boost so a higher flow IC is a big benefit, also you'll be running the 13T (assuming you don't get a Hybrid with a bigger compressor wheel made up as a cheat!) will be outside its efficiency range so you'll need to look hard at cooling, meth injection, CO2 spray onto the IC - or dry ice or water or ice - lots of possibilities really that sort of thing.

Beyond the turbo, a good set of headers and turbo back will be needed although for best power you'll loose torque at the bottom end, isolation of expansion tank from manifold, delete TB water heating etc etc

The killer for a road car is a higher stall TC, you want the stall speed up past 2500rpm for launch and that will seriously compromise road driving!

Finally you'll want to look at launch, skinnier tyres will reduce drag AND traction, so you may want to consider an MPT lock switch for best traction and running Laurals up front (same rolling radius as the rear though!) to reduce drag, launching you go effectivley RWD, you could also run a set of strip only smaller diameter tyres to further shorten the overall FDR - say 225/45/15's rear 175/70/15's at the front?

Simon
 

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none none
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9,011 Posts
13.99 is possible. We did a 14.2 on just stage 2 map. Add some more mods and a protune, I think a 13.7 is possible. 12.99, I really doubt it as we barely broke that with a vf48/mods/protune
He also has 4.44 gearing compared to the 4.11 in yours, which should make it slightly easier.

The small things will get you there, not just a downpipe and tune.
 

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Premium Member
2004 Forester XT
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923 Posts
Discussion Starter #10
Thanks all, I am going to go down the stock turbo path and see if I can pull a high second timeslip.

I like the low end torque of the TD04. Quite honestly, the upgrade path seems just as expensive as sticking with the stock turbo.

I am seriously considering the meth injection route. Biggest problem seems to be sourcing the stuff. Some say that Walmart windshield washer fluid is the way (the concentrated stuff) but I can never find that.

We will see, I have pulled off things like this in the past on my other vehicles.
Some of it does come down to attention to details.

Sooner or later I might just get there.

Thanks for all of your thoughts!
 

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2005 Forester XT 4EAT
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2,185 Posts
Idk man, with a 4eat it seems like it's gonna require a ton of work. I had a Race trans, full stage 2, Intercooler, P&P'd wrapped headers, and i don't think i broke into the 13's with that.

You'd probably have to do a seriouse port job on the TD04 to let it flow enough to work OK with the 4eat and/or an EWG and meth.
 

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Premium Member
2004 Forester XT
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923 Posts
Discussion Starter #12
Idk man, with a 4eat it seems like it's gonna require a ton of work. I had a Race trans, full stage 2, Intercooler, P&P'd wrapped headers, and i don't think i broke into the 13's with that.

You'd probably have to do a seriouse port job on the TD04 to let it flow enough to work OK with the 4eat and/or an EWG and meth.
:icon_confused::icon_frown:
 

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2005 Forester XT 4EAT
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2,185 Posts
On a side note, what stops me from going meth is I know that the second I go through the efforts of doing it, E85 will appear in my area the next day!
I think if you wanted to switch to E85 you'd have to get bigger injectors since it requires more E85 to make the same amount of power you would be making with Gasoline. IIRC a gallon of E85 contains about 2/3rds the Energy of a Gallon of Gasoline.

A good port job and EWG combined with the usual mods might put you close to your goal. I found the real probem with my TD04 was that the 4eat likes to keep the revs over 4500rpms after screaming through first gear, and the TD04 does nothing but restrict at those RPMS. So a free flowing EWG should help free up the top end, but i don't know if it would be enough.
 

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Premium Member
2004 Forester XT
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923 Posts
Discussion Starter #15
I think if you wanted to switch to E85 you'd have to get bigger injectors since it requires more E85 to make the same amount of power you would be making with Gasoline. IIRC a gallon of E85 contains about 2/3rds the Energy of a Gallon of Gasoline.

A good port job and EWG combined with the usual mods might put you close to your goal. I found the real probem with my TD04 was that the 4eat likes to keep the revs over 4500rpms after screaming through first gear, and the TD04 does nothing but restrict at those RPMS. So a free flowing EWG should help free up the top end, but i don't know if it would be enough.
Sorry, but what is an EWG?

Thanks
 

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The Sub kit guy
2005 Forester X & XT VF39
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13,100 Posts
EWG is an external waste gate.

LIke what gOOFy said, I think your tranny is going to be a problem. THe Auto tranny shift points and the TD04 just don't match very well. The TD04 is great from 2500 to 4500rpm, but the tranny likes to keep it above that range. A VF series is a much better match.
 

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Premium Member
2004 Forester XT
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923 Posts
Discussion Starter #17
EWG is an external waste gate.

LIke what gOOFy said, I think your tranny is going to be a problem. THe Auto tranny shift points and the TD04 just don't match very well. The TD04 is great from 2500 to 4500rpm, but the tranny likes to keep it above that range. A VF series is a much better match.
Ahhh, gotcha. I guess I am holding my breath waiting for some sort of TCU crack. What you are saying about the TD04 and the Auto does make sense.

Time to think about upgrading my turbo if I want to achieve this goal.

Of course, the second I do that E85 will be introduced the next day and so will some TCU controller haha! :biggrin:
 

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2004 Subaru FXT MT
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1,853 Posts
Bigger injectors are required if you wanted to switch to E85 since it requires more E85 to make the same amount of power you would be making with Gasoline. IIRC a gallon of E85 contains about 2/3rds the Energy of a Gallon of Gasoline.
^^I fixed that for you goofy:biggrin:

I ran my FXT at stg 2 on E85 for a couple weeks. I stopped because I was hitting 107% IDC @ 4400 rpm on the stock injectors...

Big injectors on E85 aren't an option. Its a requirement.
 

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4,235 Posts
how much does the car weigh? How much do you weigh?

if the car was like 2600lbs with you in it, it would probably be very feasible. it's not very feasible--financially or mechanically--without a pretty light car.
 

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2007 FSTI and X 6 MT
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22,330 Posts
He also has 4.44 gearing compared to the 4.11 in yours, which should make it slightly easier.

The small things will get you there, not just a downpipe and tune.
I totally understand this, but even my VF48 4.11 gears seems sluggish on the top end. The talled gear will hurt it on the big end. I run an 8.0 1/8 mile to a 12.9 1/4. With an 8.0, I should be in the mid 12's easy, but the 4.11 is killing it. 4.44 will only make it worse.
 
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