[Mit_Boost]

This is in response to some of the outdated and misleading N54 upgrade threads that have been posted. This thread is also an attempt to be as comprehensive as possible, covering everything from Tuning Platforms to Suspension. However, this thread will not discuss the pros/cons of each potential option. There's an abundance of threads that already speak to peoples reviews and recommendations.

Tuning
This arguably is the most important piece of the your aftermarket puzzle. Without proper tuning, you can be running what you think is a powerful setup, but instead actually be leaning on the OEM “safety nets” (i.e., knock detection and fueling tables). As a result, regardless of whether you’re just doing standard bolt-ons or chasing 800+ WHP with an aftermarket turbo, you’ll need a "foundational" flash tune to most effectively manipulate fueling and ignition tables:

• COBB AccessPORT
• MHD

In addition to the base flash tune, some people prefer to run piggybacks, whether it’s for boost management or supplementary fuel injection:

• Burger Tuning JB4
• MOTIV Boost Box
• Split Second Supplementary Fuel Management

However, only a standalone engine management will provide the most complete (i.e., maximum safe power) tuning platform. Currently, only the Syvecs S6 Plus Plug-N-Play kit offers CAN integration with a host of features (Anti-Lag from a Stop and Roll, true FlexFuel, complete aftermarket fuel system control, etc.), in addition to allow more aggressive transmission conversions and an essentially limitless amount of failsafes that can be programed. However, converting to a Syvecs standalone will be considerably more expensive than tuning with the OEM DME.
Also, depending on your power level, you should consider upgrading your ignition components:

• NGK 5992 (ILZKBR7A-8G) Spark Plugs (Gap to 0.56 mm or 0.022″)
• Bimmer Life Tuning Ignition System
• Precision Raceworks Ignition System

Note: If you’re 6AT, you should also source the Alpina or xHP transmission flash

Note: If you're 6AT, some people start experiencing transmission slip ~500 WTQ. Unfortunately, there is no proven upgrade for the OEM ZF 6HP21. As a result, you may be forced to decide between:

• an OEM 6MT conversion;
• an OEM DCT conversion; or
• the AD Engineering 4L80E Automatic Transmission swap

While no one has hit the limit of the OEM 6MT, the 4L80E has proven itself in the aftermarket community (upwards of 1,500 WHP) and that it is also a cost effective platform

Bolt-Ons
Intake
Anything that’s going to get your turbos more air. You can go for something simple (Burger Tuning or cp-e DCIs), an open element filter (aFe Magnum Force Stage 2 or Injen DCI), or something closed (Dinan Carbon Fiber Cold-Air or aFe Elite or Momentum Cold-Air series). However, the ultimate intake option would be replacing the OEM "pancaked" inlet and outlet tubing (i.e., restrictive) with a more free-flowing aftermarket option (Vargas/MMP/Precision Raceworks/TFT/VRSF)

Note: If you’re considering a Single Turbo conversion or Twin Turbo upgrade, Aftermarket Intake/Outlet tubing may not be necessary or compatible

Intercooler
This will be very important to help keep IATs down, especially over repeated pulls and when the weather starts getting hot. In addition, before you even look at brands you should consider whether a standard 5” or 7”+ core will be necessary (depending on your goals). I would state if you’re below 550-600 WHP, a 5” FMIC is sufficient. It’s common knowledge that a larger core will be more effective at IAT suppression, but it also comes with additional pressure drop. Accordingly, if you’re staying with OEM turbos, save some money and go with a better suited 5” FMIC.

5” Options: Active Autowerke, AMS, ARM Motorsports, COBB Stepped, cp-e, Dinan, ETS, Evolution Racewerks, Forge Motorsports, Helix Motorsports Stepped Core, Mishimoto, STETT, VRSF Stepped, Wagner Stepped

7” Options: AD Engineering, ETS, VRSF

I’ll also include in this section two other things: Charge Pipes and Diverter or Blow-Off Valves. Why? Chances are when people start running higher boost, one of these things will start to leak and, possibly, crack (especially considering some of these cars are now 10 years old).

Charge Pipe: Active Autowerke, AD Engineering, aFe, ARM Motorsports, cp-e, ETS, Evolution Racewerks

Diverter or Blow-Off Valves: Forge Motorsports, HKS, Tial, Turbosmart, etc.

Note: Most Charge Pipe vendors offer “add-on” Diverter or Blow-Off Valves with purchase, in addition to optional Meth Bungs

Exhaust
Here, it depends whether you’ll be staying twin turbo or converting to single turbo (more on that below). For those staying twin turbo, catless downpipes will help free up some ponies by eliminating the restriction created by the catalytic converters.

• Active Autowerke
• aFe
• AR Design
• ARM Motorsports
• COBB
• cp-e
• N54 Tuning
• VRSF
• Wagner

Note: Some vendors also offer “race” catted downpipe options

Some people may desire a full downpipe-back exhaust. While the resonator delete is a common “budget” upgrade, there are several more refined options:

• Active Autowerke
• aFe
• Akrapovic
• Borla
• COBB
• Corsa
• Eisenmann
• Meisterschaft
• Milltek
• OEM 335is (rear section)
• Remus
• Rogue Engineering
• Super Sprint
• Vanguard
• VRSF

Advanced
Upgraded/Supplemental Fueling
Since everyone has become aware of the clear performance benefits of ethanol fuel, upgraded and possibly even supplemental fueling has become necessary to run safely. Options range from low-pressure side bucket upgrades to fuel rails with supplemental injection or secondary high-pressure fueling.

• AD Engineering (Port Injection)
• cp-e (Port Injection)
• Doc Race (Intake Manifold with Fuel Rail)
• Evolution of Speed (Port Injection Rail and Intake Manifold with Fuel Rail)
• Fab Factory (Billet Intake Manifold with Fuel Rail)
• Fuel-It (Low-Pressure Upgrades, Stages 1 through 4, Throttle Body Injection, and Port Injection)
• MMP (Low-Pressure Upgrades, Stages 1 through 4, and Port Injection)
• MOTIV (Port Injection system)
• Precision Raceworks (Low-Pressure Upgrades, Stages 1 through 4, and Port Injection)
• Twisted Tuning
• Vargas (Shotgun High-Pressure Upgrade)
• Walbro DIY

Note: There are a variety of ways to incorporate Supplemental Injection, speak with your tuner first to confirm which system he believes works best for your setup

Note: Since true FlexFuel is available (either with Syvecs or MHD/MOTIV), it may be worthwhile to consider having a ethanol sensor installed if you're doing already doing a fuel system upgrade

Note: I have intentionally NOT listed methanol systems, but they are also recognized as a more “cost effective” (cheap) fueling “bridge”. If you're interested in running Methanol Injection, speak with your tuner about the system he believes works best for your setup

Single Turbo Conversion
This has essentially become the established “high power” performance modification. As a result, a lot of new vendors enter (and exit) the market, so I will only list the established names:

• AD Engineering
• Doc Race
• On 3 Performance
• MOTIV Motorsport

Twin Turbo Upgrades
Twin Turbo upgrades range from stock frame upgrades (i.e., upgraded compressors wheels, wastegates) to more complete aftermarket manifold/turbo combinations:

• MMP
• Pure Turbos
• RB Turbos
• The Turbo Engineers
• Vargas Turbo (offers GC/GC Lite 2.0 and VTR/VTX-R packages)

Note: Certain single turbo kits may require additional modifications (e.g., Coolant Relocation kits). Familiarize yourself with each setup to ensure your single turbo conversion isn’t unintentionally held up by missing parts

Note: Regardless of whether you're running a Single Turbo Conversion or Upgraded Twin Turbos, it would be wise to upgrade to NGK 5992 Spark Plugs and consider the Precision Raceworks Ignition System Upgrade


Intake Manifold
This is becoming a much newer “high power” performance modification. Somewhat self-explanatory, but an aftermarket intake manifold will help airflow (and as a result, improve throttle response and increase power).

• AD Engineering
• Doc Race
• Evolution of Speed
• Fab Factory

Built Engine
While we still haven't found the official limit of the OEM N54, some people want all the horsepower and some people like the comfort of building their motor before a rod "installs" a window in the side of the block.

• ABR Houston (Forged Internals, Closed Deck Block Blocks, Custom Head Work, Punisher Stroker Packages)
• AD Engineering (Forged Internals)
• MMP (Forged Internals, Closed Deck Insert, Aftermarket Head)
• MOTIV (Forged Internals, Closed Deck Insert, Aftermarket Head)
• VAC (Aftermarket Head; Stages 1-3)

General Supporting Mods
Clutch
For the Manual Transmission crowd, your clutch slip might start slipping once you go FBO. As a result, an upgraded clutch may be necessary:

• ACT (HDSS or HDG6)
• MFactory Twin Disk (Stage 2+, 3+, Twin-Disc)
• MOTIV (Twin Disc)
• OEM 335is/550i Clutch
• SPEC (Stage 2, 2+, 3)

Note: Certain clutch upgrades may require a compatible flywheel

Note: If you have a DCT, aftermarket clutches are available from Dodson Motorsport and SSP

Suspension
As great as the OEM Sport Package setup is, these cars are getting dated and you may want something worthwhile. There’s a long list of upgrades here (M3 Control Arms, Engine/Transmission Mounts and Bushings, etc.), but I’ll just list established Coilover brands:

• Bilstein
• COBB
• Dinan
• H&R
• KW
• Ohlins
• ST

And Sway Bars:

• Dinan
• Hotchkis
• H&R

LSD
The BMW E-Diff gets overpowered very easily. For those who can budget it, an LSD will even have a drastic impact on drivability

• Drexler Motorsports
• MFactory Helical
• OS Giken
• OEM E9x M3 Swap
• Turner Motorsports
• Quaife
• WaveTrac

Note: Depending on your power level, DSS or MFactory upgraded axles may be necessary

Brakes
Same idea as the Suspension and LSD. Even a few FBO pulls or spirited backroad driving can overpower the brakes. Brake upgrades fall into 2 categories:

Simple: OEM Z4 35is 2-piece Rotors, OEM F30 Performance Brake Conversion, StopTech Drilled/Slotted Rotors, Brake Pad and Brake Line Upgrades

Big Brake Package: AP Racing, Brembo, StopTech

Miscellaneous
Oil Catch Can: Prevent oil vapor from clogging up your intake track/FMIC, in addition to freeing up some HP

• AD Engineering
• Burger Tuning
• Mishimoto

Radiator: More efficient cooling

• CSF
• Mishimoto

[acegp1]

Good job being comprehensive with this write-up!

[dlbrooks18]

This is great. In addition to Alpina flash for 6AT, there is apparently an even better option now that the TCU has been cracked. The XHP flash will complement performance upgrades and can handle more torque.

http://www.e90post.com/forums/showthread.php?t=1360522

[Mit_Boost]

Originally Posted by dlbrooks18

This is great. In addition to Alpina flash for 6AT, there is apparently an even better option now that the TCU has been cracked. The XHP flash will complement performance upgrades and can handle more torque.

http://www.e90post.com/forums/showthread.php?t=1360522

This looks great and I'll add it. But does anyone have data logs that can demonstrate (1) there's no 5th gear timing flatline issues and (2) an overlay comparing shift times vs. the Alpina flash?

[Rogue-OP]

Thank you for putting this together!

Regarding tuning & flashing, I need to do both?
And is the flash customized to the current hardware setup of the car or is there a click + play flash?

[Scott16]

LSD options... You can add an M3 LSD to that one. Or go the whole hog and have an entire rear M3 subframe assembly (prop modification required) which gives better rear suspension geometry, stiffer subframe bushes, beefier driveshafts and beefier diff input shaft and will probably end up cheaper than just an aftermarket LSD.

[homemade_f81]

For the brakes, you can add F30 M Sport brakes (370mm front rotors) - can be done fairly inexpensively and are all OEM parts. Fronts are a straight bolt-on upgrade. Rears are a little bit more challenging.

[Mit_Boost]

Originally Posted by Rogue-OP

Thank you for putting this together!

Regarding tuning & flashing, I need to do both?
And is the flash customized to the current hardware setup of the car or is there a click + play flash?

I'm more familiar with COBB, in which case you can download "Off The Shelf" (OTS) maps which designate what mods you'll need (Intake Only, Intake + FMIC, etc.). Each level then has a 91, 93, and 100+ Octane setting, but all the OTS maps are kept very conservative.

If you want the best performance and drivability, you'll need a tuner to clean up the tune and refine the various parameters (fueling, ignition timing, boost, etc.).

[Jklad]

Originally Posted by Rogue-OP

Thank you for putting this together!

Regarding tuning & flashing, I need to do both?
And is the flash customized to the current hardware setup of the car or is there a click + play flash?

No need for both. Just get mhd with custom tune and be done. Coming from someone with an outdated Cobb.

[hellokitty]

Good job - this should be stickied.

[NoGuru]

I'm surprised more people are not adding info to this. Good work!

[Mit_Boost]

7/2017 -- Updated to reflect AD Engineering 4L80E Automatic Transmission, Fab Factory Billet Intake Manifold, established Twin Turbo Upgrades and Built Motor vendors

[Antoans4]

Originally Posted by swedishpowah

For the brakes, you can add F30 M Sport brakes (370mm front rotors) - can be done fairly inexpensively and are all OEM parts. Fronts are a straight bolt-on upgrade. Rears are a little bit more challenging.

Rotors and pads from F30 335i with Msport package?

[autoart]

I did not see anything for inlets and hotside outlets?

[Mit_Boost]

Originally Posted by autoart

I did not see anything for inlets and hotside outlets?

Briefly mentioned in the "Intake" section

[homemade_f81]

Originally Posted by Antoans4

Rotors and pads from F30 335i with Msport package?

It's an excellent upgrade and can be done fairly inexpensively. Don't know why it's not on the list.

Discussed in a lot of detail here:
http://www.e90post.com/forums/showthread.php?t=828362

[Mit_Boost]

Originally Posted by swedishpowah

It's an excellent upgrade and can be done fairly inexpensively. Don't know why it's not on the list.

Thanks, I had heard of this an the Cadillac CTS-V conversion but couldn't find concrete answers on whether either were possible. Added

[Antoans4]

Originally Posted by swedishpowah

It's an excellent upgrade and can be done fairly inexpensively. Don't know why it's not on the list.

Discussed in a lot of detail here:
http://www.e90post.com/forums/showthread.php?t=828362

How much would it cost

[Faredo]

bump to replace sticky FROM 2008!

[Torgus]

missing a very popular diff

nice write up for the most part.

[Mit_Boost]

Originally Posted by Torgus

missing a very popular diff

?? Always looking to add stuff

[rayrobot]

nice update. Would be looking into this same thread many times in the future! Maybe add in an 335xi section as well?