BrenTuning | 2015+ STi development thread

[BrenTuning]

At BrenTuning we have been focusing a lot of our attention on the 2015 WRX, but that doesn't mean we have abandoned the STi. The 2015 STi is very impressive with mods ranging to our typical stage 1 or stage 1+ setup all the way to our stage 3 setup. This thread will detail the cars that come through our shop, the mods that have been performed and the numbers/gains that were found!

Just a quick run down on which parts go with which stage:

Stage 1:

Stage 1 is perfect for someone looking for some extra power, better fuel economy, improved drivability and more safety over the OEM mapping. Our typical stage 1 cars are in the 270-280WHP range with torque around 300WTQ.

- Stock car
- Cobb Accessport
- Stage 1 PROTune

Stage 1+:

Stage 1+ is a great option for those who want a little more power and sound over our Stage 1 mapping. The Cobb SF intake is our intake of choice with which we have found the best and most reliable gains. Other intakes will work, but Cobb provides great products that are well tested, they are always our go to! Expect to see gains of 15WHP/WTQ over our Stage 1 mapping.

- Cobb SF Intake
- Cobb Accessport
- Catback exhaust (optional)
- Stage 1+ PROTune

Stage 2:

Stage 2 is the next step. This includes an aftermarket catted or catless downpipe in addition to an aftermarket intake. A stock intake and catback exhaust can be used with this setup, but to maximize the setup, we recommend an aftermarket intake/catback be used. We prefer the Cobb catted downpipe but there are many alternatives that provide similar results. Our typical stage 2 cars are in the 300WHP/330WTQ range +/- depending on parts selection.

- Cobb SF Intake
- Cobb Accessport
- Catted downpipe
- Catback exhaust (optional)
- EBCS (Cobb preferred)
- Stage 2 PROTune

Stage 2+:

Stage 2+ is for those who are looking to maximize the stock turbo and fuel setup. Any goals beyond this will need additional fueling (ID1000 injectors) as well as a bigger turbo. This will max the stock turbo and place the car in the 330WHP/360WTQ range with many cars being torque limited due to the stock clutch. We have seen cars close to 400WTQ with upgraded injectors, intercooler and EBCS on the stock turbo. Horsepower doesn't go up all that much but add the above listed mods and you can make more torque if you truly want to maximize your pump gas stock turbo car!

- Cobb SF Intake
- Cobb Accessport
- Catted downpipe
- Catback exhaust
- Equal Length header
- EBCS (Cobb preferred)
- Stage 2+ PROTune

Stage 3:

This is the ideal reliable and discreet stock block setup. With these few mods and a few days at our shop, you can transform your STi into a street monster. We have replicated this same setup for a few customers and they have all been extremely pleased with the results! You'll get stock like drivability and spool with a massively improved top end. The stock turbo is out of breathe in the higher RPMs, that is where the Blouch 1.5XT-R shines. Top end gains of 100WHP have been seen, this translates to a car that just keeps pulling until redline. Depending on your exact setup we would expect numbers in the 350-380WHP range. This setup can be done on a budget by utilizing the stock exhaust manifold and intercooler, however, we always recommend upgrading both at this power level! For those of you looking to build your block down the road and go for more power, you can opt for the Blouch 3.5XT-R. From our testing we found spool almost identical to the 3.5XT-R, you can find the dyno graph comparison in post #14 of this thread!

- Cobb SF Intake
- Cobb Accessport
- Catted downpipe
- Catback exhaust (optional but preferred)
- Equal Length header (optional but preferred)
- Blouch 1.5XT-R 2.4" 10CM (3.5XT-R optional, 3" inlet required)
- ID1000 Injectors
- DW65C Fuel pump
- Grimmspeed Top mount intercooler (or equivalent; optional but preferred)
- '07 STi Fuel pressure regulator
- Stage 3 PROTune


Contact:

Email: [email protected]
Phone: 508-762-1769
Facebook: Facebook.com/brentuning
Instagram: @Brentuning



Stage 1-3 Dyno overlay



Stage 1-2+ dyno overlay

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[BrenTuning]

Stage 1

Car: 2015 STi
Tuner: BrenTuning
Dyno Info: Mustang MD150
Transmission: 6-Speed
Gear: 4th
Peak HP at RPM: 271WHP @ ~5500RPM
Peak Torque at RPM: 300WTQ @ ~4000RPM
Baseline HP/TQ for stock on same dyno: 2015 STi - 250WHP/250WTQ
Target Boost: 19PSI
Target AFR: ~11.0
Fuel: 93 Octane

Contact:

Email: [email protected]
Phone: 508-762-1769
Facebook: Facebook.com/brentuning
Instagram: @Brentuning


Chris brought in his 2015 STi completely stock for us to tune to stage 1. This car came in with 1400 miles, on the OEM fill oil fill and was 100% stock down to the air filter. Chris had the Accessport in the glovebox and had never been flashed. The car baselined very low compared to the other 2015 STi's that we have had in the shop at 236WHP/217WTQ. We only did one pull on the stock map, it is possible with a few more pulls the power could have been higher. After putting our map on and making a some pulls to optimize the map, we achieved final numbers of 271WHP/300WTQ! Timing was kept lower than normal per the customers request, there was some power left on the table for sure.

[BrenTuning]

Stage 2

Car: 2015 STi
Tuner: BrenTuning
Dyno Info: Mustang MD150
Transmission: 6-Speed
Gear: 4th
Peak HP at RPM: 306WHP @ ~5750RPM
Peak Torque at RPM: 336WTQ @ ~4250RPM
Baseline HP/TQ for stock on same dyno: 2015 STi - 250WHP/250WTQ
Target Boost: ~20PSI
Target AFR: ~11.0
Fuel: 93 Octane

This 2015 STi came in for a Stage 2+ tuning. The car baselined 279WHP/297WTQ on our in house Mustang Dyno with Cobb OTS Stage 2 mapping. After spending time on the dyno honing in the map, we found the best combination of power and reliability. The cars final map came out to 306WHP/336WTQ with a safe and reliable 10.9-11.0AFR and only at 20PSI.

[BrenTuning]

Stage 3

Car: 2015 STi
Tuner: BrenTuning
Dyno Info: Mustang MD150
Transmission: 6-Speed
Gear: 4th
Peak HP at RPM: 370WHP @ 6350RPM
Peak Torque at RPM: 350WTQ @ ~4650RPM
Baseline HP/TQ for stock on same dyno: 2015 STi - 250WHP/250WTQ
Target Boost: 20PSI
Target AFR: ~11.0
Fuel: 93 Octane

Vito came to us with his 2015 STi for us to build him a perfectly reliable, quiet, powerful and emissions friendly daily driver. The mod list is very simple and that was the goal, keep everything is basic as possible while still making reliable power on the stock longblock. One of our favorite turbos at BrenTuning is the Blouch Dom 1.5XTR. This turbo provides basically stock like spool with amazing gains throughout the whole rev range and a massively improved top end. As you can see in the graph below, spool is almost exactly the same as our stage 1 tune on the same car with gains of over 100WHP at redline. As far as the tune on this car, it is at 20PSI with AFR at 11.0. Timing was kept low and the car was built with reliability and longevity in mind. We could definitely pushed the car further and made higher numbers, but there was no need. This setup is quick enough for a daily driven street car!

This is the ideal setup for the street and this package can be easily replicated. If you are looking to do something similar on a lower budget, you can go with the stock exhaust manifold or a different EL header, we do really like the KillerB header and definitely helps complete the package and keep spool the same as stock! The car has a Cobb catted DP which tapers to 2.5" and a Corsa Catback which keeps everything fairly quiet for a 370WHP car. No sensors have been messed with, the stock clutch and inlet were used and the car is still on MAF.

Baseline stock: 252WHP/245WTQ
Stage 1 Protune: 271WHP/270WTQ

Contact

Email: [email protected]
Phone: 508-762-1769

Mods

- Stock longblock, Stock clutch, Stock inlet etc
- Blouch Dom 1.5XTR 2.4" inlet 10cm Hotside internally gated
- KillerB Holy Header
- Grimmspeed TMIC
- Cobb SF intake w/ Box
- Cobb Catted DP
- Corsa catback exhaust
- ID1000
- '07 STi FPR (fuel stumble)
- DW65C Fuel pump
- KillerB Pickup tube
- Cobb Accessport







1.5XTR vs BrenTuning stage 1

[BrenTuning]

Stage 1+

Car: 2015 STi
Tuner: BrenTuning
Dyno Info: Mustang MD150
Transmission: 6-Speed
Gear: 4th
Peak HP at RPM: 301WHP @ ~6150RPM
Peak Torque at RPM: 318WTQ @ ~3950RPM
Baseline HP/TQ for stock on same dyno: 2015 STi - 250WHP/250WTQ
Target Boost: ~19PSI
Target AFR: ~11.0
Fuel: 93 Octane

Ian came to us with his beautiful bagged '15 STi for a PROTune! The car came in equipped with a Cobb SF intake and Invidia Q300, nothing else. We have tested most of the intakes for the '15 on the market and always find that Cobb performs the best. It is the most consistent and always seems to make the best numbers, also great quality and fitment is perfect as you would expect from Cobb. This car put down an easy 301WHP and 318WTQ which makes for a great, reliable DD!

Stock vs Stage 1+

[BrenTuning]

This car ^^^^^^^

Ian came back for more tuning after installing another round of modifications on his beautiful, bagged '15 STi. As seen in post 5, he previously had a Cobb SF intake and Invidia Q300 catback and posted some very strong numbers for a stage 1+ car. This time he added:

Catless Downpipe
KillerB EWG Header
Tial 38MM EWG
DW65C
ID1000

This is basically our ideal stock turbo setup and could put a hurting on many other upgraded turbo cars. The KillerB header proved to make 30WHP/30WTQ over every other similar (stock manifold) setup we had done prior. While they are pricey, the performance speaks for itself.

Below is his stage 1+ setup we tuned a few months back vs the current setup. Notice the boost curve and that the car is at a lower boost level while making 30+WHP/45WTQ more. This is on 93 octane in 85*+ weather, previous tune was done in winter.



Chris

[BrenTuning]

Stage 2+ FlexFuel

Car: 2015 STi
Tuner: BrenTuning
Dyno Info: Mustang MD150
Transmission: 6-Speed
Gear: 4th
Baseline HP/TQ for stock on same dyno: 2015 STi - 250WHP/250WTQ
Peak HP at RPM (91): 315WHP @ ~4700RPM
Peak HP at RPM (E72): 348WHP @ ~5350RPM
Peak Torque at RPM (91): 347WTQ @ ~4700RPM
Peak Torque at RPM (E72): 402WTQ @ ~4200RPM
Target Boost (91): ~20PSI taper to 16PSI
Target Boost (E72): ~21PSI taper to 16.5PSI
Target AFR (91): ~11.1 taper to 10.9
Target AFR (E72): ~11.7 taper to 11.1
Fuel: 91 and E72 (FlexFuel)

We had a stage 2 + EL header 15 STi some in the other day for some FlexFuel love! The car had 91 octane in the tank since it is getting shipped to Arizona in a few months. The car is ridiculous on E72 (NE winter blend) making over 400WTQ. The FlexFuel kit is very complex but works flawlessly. I can definitely understand why there was a such a delay in launching it. Cobb never releases something that is less than 100% perfect.

Modifications include:

COBB 1000cc injectors
Aeromotive 340LPH fuel pump
Invidia EL header
Grimmspeed up-pipe
Grimmspeed limited catted downpipe
Invidia Q300
Cobb SF W/ Box

[BrenTuning]

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[BrenTuning]

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[BrenTuning]

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[BrenTuning]

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[BrenTuning]

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[fourmicah]

Impressive write up and research. Thank you for doing the work and letting us know what works.

[BrenTuning]

Originally Posted by fourmicah

Impressive write up and research. Thank you for doing the work and letting us know what works.

No problem!

Here is an interesting comparison! While this is a GR WRX vs VA STi, it really shows that the bigger Blouch turbos don't compromise spool. We installed a 3.5XTR on a low mile '11 WRX with basically an identical mod-list to the "Stage 3" '15 posted above. The biggest difference would be the KillerB header ('15) vs Agency Power EL ('11). The 3.5XTR is only at 18PSI and the 1.5XTR is at 20PSI. Power numbers are almost identical while being at lower boost levels with negligible difference in spool. The 3.5XTR is really a great option for those of you who would like to shoot for more power down the road while still having a very streetable stock block car!

[Cflo23]

Interested in a Stage 1+ PROTune or should I say E-Tune... I'm located in California.

[BrenTuning]

No problem shoot us an email [email protected]

[shoots808]

I'd like to see the comparions of those on E85

[BrenTuning]

E85 would be significantly higher for sure. The goal of the stage 3 package is to be reliable on the stock block, at power levels above 400WHP there are many variables to keeping the shortblock together. The 3.5XT-R car is only at 18PSI, we have tuned them on pump gas in the 24PSI range and 440WHP, fuel quality is not the holding back point on that turbo.

[shoots808]

Would you be able to do mulitple maps for instance daily driving on 93, and then have a E85 map for track/spirited driving?

Also these maps would be safe for maintaing a upgraded topmount, turbo, fuel injectors, fuel pump?

[BrenTuning]

Originally Posted by shoots808

Would you be able to do mulitple maps for instance daily driving on 93, and then have a E85 map for track/spirited driving?

Also these maps would be safe for maintaing a upgraded topmount, turbo, fuel injectors, fuel pump?

Hello,

We could! But one thing we are not offering at the moment is remote E85 tuning without a Cobb compatible FlexFuel sensor. We do not feel it is a consistent enough fuel to be safe for our customers. For example, the local pump here has measured out from anywhere between E85 to E25.

We can tune for any of those modifications. We just need to know the full mod list when purchasing a tune. If adding those parts after we tune, the tune will need to be revisited.

[email protected]

[shoots808]

Not a problem, just curious what the conditions were for that to be possible. Thank You!

[carlos.danger]

Originally Posted by BrenTuning

Hello,

We could! But one thing we are not offering at the moment is remote E85 tuning without a Cobb compatible FlexFuel sensor. We do not feel it is a consistent enough fuel to be safe for our customers. For example, the local pump here has measured out from anywhere between E85 to E25.

We can tune for any of those modifications. We just need to know the full mod list when purchasing a tune. If adding those parts after we tune, the tune will need to be revisited.

[email protected]

when this happens, does the AP know to adjust for less potent blends? or does the user have to know to back off until the bad tank is gone?

[BrenTuning]

Originally Posted by carlos.danger

when this happens, does the AP know to adjust for less potent blends? or does the user have to know to back off until the bad tank is gone?

There is no way, as of now, for the AP to change the map based off of ethanol content. Cobb is working on a true flexfuel solution which would give the ability to pump ethanol and the tune will be changed accordingly based off of ethanol percentage.

[email protected]

[carlos.danger]

^ gotcha.

one more question.

how do you guys like the AP stage 1 OTS tune? are you having to modify it much?

[BrenTuning]

Originally Posted by carlos.danger

^ gotcha.

one more question.

how do you guys like the AP stage 1 OTS tune? are you having to modify it much?

We develop our files from scratch.

[email protected]