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2006 Forester XT 6MT 07 STI 6MT - Complete 5x114 drivetrain swap
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Discussion Starter #1
I've been lurking around looking for information and haven't found any definitive answer for my particular configuration.

I have a 2006 FXT 5MT and I want to install a VF43 and STI TMIC. I don't have an upgraded TBE yet. I'll probably get one when I've saved up enough money which could be a few months.

My question is, can I use the COBB VF39 map with a VF43 and STI TMIC with stock TBE? Also, will I need to drill out the VF43 pill or can I use the stock pill?
 

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2004 Forester XT '06 STi 6MT
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the stage 1 map is as high as you can go on the stock exhaust system.

stage 2+ (including the vf39 maps) require at least a downpipe, though a full exhaust is recommended and pretty standard.

i would buy the full exhaust now and go stage 2 on the stock turbo/tmic. it will be a very nice increase in power and should have some lasting fun factor.

if you do go vf43 you really need a protune on the AP. cobb's vf39 map is just that, ONLY optimized for the vf39.
 

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2006 Forester XT 6MT 07 STI 6MT - Complete 5x114 drivetrain swap
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67 Posts
Discussion Starter #3
I was hoping to install the turbo and tmic already. I guess I'll have to wait.

I thought the VF43 is almost the same as a VF39 which is why some people use the VF39 map on their VF43s?
 

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2017 VW Golf SportWagen 5MT
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Save yourself the headache and potential issues and install everything at once. I'd use the VF39 map to pretty much just limp to a tuner, I wouldn't use it as my only map. Don't touch the pill.

Stan
 

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2004 Forester XT '06 STi 6MT
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I was hoping to install the turbo and tmic already. I guess I'll have to wait.

I thought the VF43 is almost the same as a VF39 which is why some people use the VF39 map on their VF43s?
do it right or do it twice. just because you see/read about people doing it on the internet doesn't mean it's the correct way to do it. is it really worth the risk of possible engine/turbo damage by running a generic map? every car is different and every car reacts to cobb's maps differently. for example, i actually get better gas mileage on my stage 1 map than a lot of other people do.

i would save up for the exhaust and throw that on FIRST. a full exhaust + stage 2 map on the stock turbo/tmic is a very serious difference in power compared to the stock setup. it's so easy to go that route that if you're dying for more power. then save up to do the vf43 setup which will be easy since you already have the full exhaust. that's the progressive way to do it if money is an issue. otherwise save up and do it all correctly at once.
 

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2004 FXT
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952 Posts
I ran the VF39 OTS map on a VF43 + STi TMIC for about a week and a half before I got it tuned. You'll notice that it runs lean (you can smell the gas when you park it). Only use while you get a tune scheduled.
 

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2017 VW Golf SportWagen 5MT
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Let's put it this way -- until you get your car to a professional that can verify it's running well and make necessary tune tweaks, there is only guessing. Would you want to be pushing your car while not being sure it's safe to be pushed?

Stan
 

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The Sub kit guy
2005 Forester X & XT VF39
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If you install a VF43 and an STi TMIC but leave the stock downpipe, you basically end up with an STi. I'd run something like an STi stage 1 map.
 

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2006 Forester XT 6MT 07 STI 6MT - Complete 5x114 drivetrain swap
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Discussion Starter #9
Thanks for the help everyone! I'll just wait to install the TBE and run a stock STI map until I get it to the tuner.
 

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2004 Forester XT
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320 Posts
I don't even know where to start with all the false info in this thread.

Go ahead, run the map. I can get into it more later on, don't have the time right now.
 

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2004 FXT MT
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I ran the VF39 OTS map on a VF43 + STi TMIC for about a week and a half before I got it tuned. You'll notice that it runs lean (you can smell the gas when you park it). Only use while you get a tune scheduled.
I got lost here. Lean means low gasoline proportion compared to air, correct? If its less gas, how can you smell it? Don't you mean rich mixture?
 

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2006 Forester XT 6MT 07 STI 6MT - Complete 5x114 drivetrain swap
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Discussion Starter #12
I got lost here. Lean means low gasoline proportion compared to air, correct? If its less gas, how can you smell it? Don't you mean rich mixture?
I think he meant rich too.

I don't even know where to start with all the false info in this thread.

Go ahead, run the map. I can get into it more later on, don't have the time right now.
Now i'm confused again.. :crazy:
 

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1999 Forester S Turbo 5MT
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I don't even know where to start with all the false info in this thread.

Go ahead, run the map. I can get into it more later on, don't have the time right now.
Hi Mark. I see you are studying econonics but you don't list your car tuning experience/qualifiactions in your profile other than "self tuned". I think you'll find your opinions or advice accepted more readily and productively if you serve them a little more gently rather than just rubishing what other people have to say, without qualifying your rather derogatory comebacks? I have come across your entries quite a few times so I am not just referring to this thread and the answers you give often just seem to confuse the person asking the question. Many of the posters whose contributions you negate have a track record of positive and helpful advice, but the majority of them, especially the more "mature" ones who are qualified, do show respect.
 

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Premium Member
04 Acura TSX the slick 6 speed
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Thanks for the help everyone! I'll just wait to install the TBE and run a stock STI map until I get it to the tuner.
Don't be confused, your own statement here is the right thing to do if you want to do it right and be safe, assuming you install the new turbo/TMIC with the TBE all at once and then flash the Cobb map. This way, your car will run well for many years to come.
 

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2004 Forester XT
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320 Posts
Hi Mark. I see you are studying econonics but you don't list your car tuning experience/qualifiactions in your profile other than "self tuned". I think you'll find your opinions or advice accepted more readily and productively if you serve them a little more gently rather than just rubishing what other people have to say, without qualifying your rather derogatory comebacks? I have come across your entries quite a few times so I am not just referring to this thread and the answers you give often just seem to confuse the person asking the question. Many of the posters whose contributions you negate have a track record of positive and helpful advice, but the majority of them, especially the more "mature" ones who are qualified, do show respect.
People usually read written words in a harsh tone. So I'll cut you some slack.

I'm not an donkey, I've meet plenty of people on this board in person, who can vouch for that.

I've been tuning subarus now for 2ish years. I'm not an expert by any means, but know enough to explain why a lot of the info in this thread is false.

Running a vf39 map with a vf43 is completely fine. The turbos are basically identical. Saying the car will run "lean" is false. Fuel is calculated by how much air is traveling through the maf, the vf43/39 is well within the stock maf range. If the car is running lean or rich, it is because of a post maf leak or boost leak, which would cause a lean or rich condition if he was on the 43, or the stocker.

Ignition timing is already cut back for the vf39 tune, so considering the vf43 flows the same, he's all set there.

I've also found that with the cars I've tuned, the 43 and 39 use exactly the same wastegate cycles as well.

The good info in this thread though, is that yea, you'll get much more benefit out of a protune. Therefore the tuner can really dial in your fuel/timing/ and wastegate cycles. The cobb maps are very generic, but very safe. Your motor will be fine if you decide to stay with the ots map for a while. But you're definitely leaving some power on the table:banana:

And as far as seeing my "harshness" in the past....I'm assuming you're talking about the ebc thread. I know Cannonshooter personally, and have talked tuning with TheFoos in the past. A little razzing never hurt anyone:biggrin:

But I'm from Mass, people say we're a little more "blunt" with others.
 

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2004 FXT
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I got lost here. Lean means low gasoline proportion compared to air, correct? If its less gas, how can you smell it? Don't you mean rich mixture?
yeah, ment rich. sorry. but after reading over the post above, i'm going to go in and have it checked out to see why I do smell gas.

Thanks for that post BTW, it was very informative (atleast to me)
 

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2004 Forester XT
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yeah, ment rich. sorry. but after reading over the post above, i'm going to go in and have it checked out to see why I do smell gas.

Thanks for that post BTW, it was very informative (atleast to me)
No problem.

I'd safely bet you have an evap leak somewhere. Does it smell like gas towards the front of the car, or towards the rear?

If it's the front I'd check for cracked lines around the evap solenoid. If it's the rear, does the smell get stronger when you open the rear hatch? If it does, check to make sure the cover that houses the fuel pump is sealed properly.

If it smells towards the rear of the car from the outside, you may have a cracked evap canister, or one of the lines running from it could be dry rotted/cracked. Having a shop do a smoke test should find your problem very quickly.

Might as well do a visual check to see if the problem is blatantly obvious before shelling out money to a shop.
 

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2006 Forester XT 6MT 07 STI 6MT - Complete 5x114 drivetrain swap
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Discussion Starter #18 (Edited)
So, once it get my upgrades done:

- VF43 turbo
- STI TMIC
- Cobb 3" downpipe
- Stromung 3" catback

I'll be able to use the Cobb AP stage 2 OTS 2007 STI map until I get myself to a tuner, right?
 

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04 Acura TSX the slick 6 speed
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^^Better to use a VF39 map if you swapped to the 43.
Affirmative because the stage 2 map is set for the stock turbo, if you go with the 43 you have another turbo, the 39 map will be closer to you setup than the stage 2 map.
 
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