What sets Nostrum apart:
- Direct Replacement
- Application "side specific" spray pattern
- Limited Lifetime Warranty
- Detailed Installation guide provided
- Tuning guide available
- 1000cc/min (66% Flow rate increase vs light blue injector)
- Ethanol Compatible
Introducing Nostrum's High Flow Injectors for EJ powered Subarus!
Our upgraded injectors have been designed and tested to flow 1000cc/min, which is roughly 66% more fuel than the stock WRX 565cc “dark blue” injectors. That additional fuel flow allows for a significant increase in horsepower, with proper tuning. These are a great cost effective option for those with VF series turbos and who want to run E85!
Being that our injectors are installed like a factory part, there’s no need for adapters, aftermarket fuel rails, spacers, or additional headache! To make it even easier, we took the guesswork out and provide you with a full color and detailed installation guide. Anyone can install their own injectors in a single day!
When you are ready to tune, we have Cobb tuning guides available for your dealer or tuner. Open source tuning support is available on a case-by-case basis. These tuning guides are developed by our in-house calibration team on-dyno and on-road! We worked extensively with software companies like Cobb to validate their tables and make sure everything needed is there to run these injectors perfectly in your Subaru!
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.
Vehicle application list:
- 2002 – 2014 Impreza WRX
- 2004 & 2005 STI (with top feed conversion)
- 2006 – 2021 STI
- 2004 & 2005 Forester XT (with top feed conversion)
- 2006 – 2013 Forester XT
- 2005-2009 Legacy GT/Outback XT (with top feed conversion)
Recommended tuners:
- Clark Turner
- Accelerated Kontrol Dynamics
Dyno graph sponsorship results:
*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.
Frequently ask questions:
Q: What does “side specific spray patterns” mean? How come other manufacturers don’t have that requirement?
A: One of the main issues with aftermarket injectors is that they are universal, meaning they are not necessarily designed for the applications they are being used in. If your injectors aren’t aimed correctly, the performance you actually experience might be different than what was promised.
Our EJ injectors have been expertly developed for this application, with a twin arc spray pattern aimed directly at the back of the intake valves, to ensure you are getting the absolute most out of your injectors! We have color marked the injectors to help make sure they are installed on the correct side of the engine. Be sure to use the included installation guide!
Q: Why do your numbers say I will make less horsepower on E85 than 93 octane?
A: Great question! The numbers we list in the product descriptions are similar to the numbers a turbo charger lists for air flow. The numbers are the "fuel system capacity to generate power" regardless of the other engine system limitations (air handling, mechanical limitations, knock propensity). Essentially the numbers are calculated assuming "sufficiently large air flow", "sufficiently capable mechanical assemblies" and disregarding knock limits. The equation uses actual observed engine volumetric efficiency (when available from sponsorship vehicles) and fuel capacity (including target pressures) to calculate power. Gasoline has more energy per mass volume than E85. So the higher fuel flow capacity will mathematically generate higher power potential for a gasoline than a high ethanol content fuel. The other variables (air flow, spark, rotating assembly strength, charge cooling, mechanical assembly strength) are highly variable from build to build. This is why we state horsepower capacity for the fuel system – representing the potential of the fuel system if you have all the other aspects of your build addressed!
Q: 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.
