What sets Nostrum apart:

• +85% Larger than stock  

• +31% larger than EU5 M5 injectors  

• +19% larger than the stage 2 injector  

• Direct Fit, no harness or spacers required 

• OEM decoupling rings pre-installed 

• Ethanol compatible 

• OEM comparable spray pattern 

• Every injector is tested statically and dynamically to ensure best quality product and set batching 

• Includes comprehensive installation guide 

They’re finally here! The long awaited Stage 3 injectors for the N55 & S55 are now available! Flowing a ridiculous 85% more fuel than the stock injector while still maintaining a 250bar operating pressure rating, the Stage 3’s are what you want when you have a 4 digit horsepower goal in mind. Developed to have an OEM equivalent spray pattern, the Stage 3’s deliver unparalleled performance without sacrificing idle quality or drivability.  

Being that everything is installed like a factory part, there’s no need to worry about secondary injection controllers, filling meth tanks, clogged meth injectors, or any of the other complex solutions that remove layers of protection and safety from your engine. Our injectors operate with all the OEM ECU’s engine management system diagnostics and safety functions – resulting in a much happier and responsive system! 

Inside the box, you will find everything you need to get your new injectors installed quickly, including pre-installed decoupling rings and detailed instructions for a no nonsense install. When you are ready to tune, we can get you set up with one of our trusted certified tuners, or we have injector tuning data available for your existing dealer or tuner.  

Take your Nostrum Stage 3 injectors to the limit by pairing them with our S55 HPFP upgrade kit, flowing an incredible 36% more fuel than the stock pumps! That additional fuel flow allows for significant torque increases earlier in the rev range, and provide the injectors with all the fuel they need to make more peak horsepower, when properly tuned. 

Every Nostrum manufactured part is backed by a limited lifetime warranty. Our products are comprehensive solutions that come complete with everything you need inside the box, including detailed installation instructions. Tuning guides are also available for your dealer or tuner. We have customer service and calibration engineers on staff to provide you with any support that you may need, from installation to tuning.

Frequently ask questions:

Will these also fit an S63?

Yes, but they are batched in sets of 6. For sets of 8, see: S63 Upgraded Injectors

I see a lot of mentions about OEM equivalent spray patterns. What does that mean and why is it important?

While increasing flow rate is critical to making more horsepower, there are other factors to consider when choosing fuel system upgrades. A bigger injector isn’t always a better injector! It can flow a large volume of fuel at WOT, but if the spray pattern is poor, you can expect poor idle quality, poor drivability, increased knock propensity, soot, NVH (noise vibration harshness,) and tuning difficulty. Additionally, the wrong spray pattern can result in liquid fuel impinging in the cylinder walls, causing oil dilution, which increases mechanical wear to internal engine components.

Nostrum has invested significant time and resources into acquiring the equipment and machinery necessary to deliver an OEM level of quality on our injectors. Our spray patternation and arc flash machines (images below) give us an unparalleled look at how an OEM injector is designed and how it operates.  Our engineers design and develop injectors to optimally interact with engine air flow inside the combustion chamber to improve fuel evaporation and create a homogenous air-fuel mixture that results in a higher combustion quality. For you, this means that you can expect our injectors to perform at their absolute best regardless of what you are asking from them, from daily driver duty to setting new ¼ mile records.

Vehicle application list: 

• 2015-2018 BMW F82/F83 M4 

• 2015-2018 BMW F80 M3 

• 2016-2019 BMW F87 M2 Competition/CS

• 2016–2018 F87 M2 (Non-Competition)

• 2013–2016 F32/F33/F36 435i 

Recommended tuners: 

• Bend Calibration

• David Shoup

• Paul Johnson Tuning

• HCPerformance Tuning

• Cary Jordan

Dyno graph sponsorship results:

901 WHP & 773 lb/ft on E85, direct injection only! 

• Nostrum Twin 1050-250 pumps

• Nostrum Stage 3 S55 injectors

• Dorch Lift Kit

*Horsepower and Torque numbers are approximate and can vary significantly depending on numerous factors including what supporting upgrades are done to the vehicle, ambient temperature, elevation, road surface, tire selection & condition, fuel octane and quality, vehicle weight, and more.  The advertised numbers herein are based on optimal conditions and utilizing proper supporting modifications.  Your results may vary.