Port Injection Fuel Kit for MS3

Its 2021, you survived 2020 and finally got those last goodies installed on your Mazdaspeed 3…you’re finally fully bolted.  It’s been about 6 months and now you want more, but your Tuner keeps telling you you are out of fuel. What the Hell does that mean!?

Let me tell what that means and let me show you the solution via the BEST Port Injection Fuel Kit for your Mazdaspeed 3 or MPS 3.  If you know this is the kit for you don’t wait any longer (Link to ALL THE FUEL), but I do invite you to check out the great information below. 

Mazdaspeed 3 8th Port Auxiliary Fuel Kit

Say no to “out of fuel” and say yes to enough fuel to support 750+WHP!  But first let’s take a step back to understand the basics. 

Why is your Mazdaspeed 3 “out of fuel”?

The Mazdaspeed 3 and 6 use early technology for direct injection injectors which sadly do not have an aftermarket replacement and reach their flow capacity limit quickly.  This basically puts a limit on the OEM fuel systems horsepower capacity.  From what we have seen firsthand and in the community; the limit is around 360-390whp depending on the performance parts on the engine and the fuel used.  The only current solution is to add a port injection system with either 2 extra or 4 extra injectors.  We’ll talk more about that. 

Mazdaspeed 3 8th Port Auxiliary Fuel Kit

What is an auxiliary port injection fuel system? – This is a kit that adds (does not replace) port style fuel injectors to the intake manifold so that you can increase the total fueling capacity of your Mazdaspeed or MPS.  There are a few ways this can be done and all have been done in the Mazdaspeed Community. 

2 extra or 4 extra injectors (aka 6th Port or 8th Port Injection)

While the CorkSport Port Injection Fuel Kit is designed for 4 extra injectors (8th Port Kit); there are options in the community that only use 2 extra injectors (6th Port Kit).   CorkSport believes the 8th Port Injection kit is the superior setup because it has higher capacity, is more reliable and safer for the engine.

With an 8th Port Kit there is an extra injector on each runner of the intake manifold spraying directly into that one and only runner.  With a 6th Port Kit there are two extra injectors spraying directly ahead of the throttle body and then depending on the flow distribution of the intake manifold to disperse the fuel to each runner and thus cylinder.

Return vs Returnless Setups

This is another option for Port Injection Fuel Kits in the community.  While both have their place, the CorkSport 8th Port Fuel Kit uses a “return” style setup because again it has higher capacity, is more reliable and safer for the engine because it is easier to tune for.

In a “return” style setup the fuel pressure for the extra injectors increase as boost pressure increases keeping a consistent fuel flow rate per injector duty cycle which provides the higher capacity and much more consistent tuning.  While the “returnless” style setup just plumbs the extra injectors into the OEM fuel feed to the HPFP.  The fuel pressure does not increase with boost pressure and therefore the capacity is lower, around 500-550WHP.

Integrated vs Standalone Fuel System

Lastly is the consideration of how the Port Injection Injectors are fueled.  This can come from the OEM fuel tank or from a completely separate fuel tank in the vehicle.  Unlike the bullets points above, this is not really a “one is better than the other”, but more of “what suits the needs of your vehicle and uses”. 

Integrated Setup

As the name implies this means the Port Injection Fuel Kit sources its fuel from the OEM tank and in-tank pump.  This can actually be done a couple ways 1) via the “returnless” setup as mentioned above but that has its issues or 2) via a surge tank that is mounted in the engine bay or cabin…which has some concerns.

The surge tank setup is a very common “racecar” setup and for good reason.  It handles high G load corning, acceleration, and braking great and also fuels the entire car, not just the port injection system.  However the cost is usually much higher and requires relocation of other engine bay components so you can mount the surge tank. Along with that you can only use one fuel for the entire system so if your car needs a special high octane fuel then you have to use it at all times during operation, whether cruising or full power.

Standalone Setup

In contrary this is a completely separate fuel source via a separate tank.  This can be a really great option for the enthusiast that does some spirited driving, maybe some events here and there, but also daily drives their Mazdaspeed 3.  How is this the case?

With a completely separate fuel cell for the port injection system you can run the exotic race gas/ethanol in the port injection tank and run normal cheap pump gas in the OEM tank.  When you daily drive/cruise you only use the pump gas in the OEM tank and when you want power the port injection kicks in with the high octane fuel.  It’s a win/win, especially if you do not have ethanol close by and have to special order the exotic fuel like we do here in the PNW.  However this does mean you need a 2nd fuel tank for the port injection which can be a pain, BUT CorkSport has that covered in this complete kit

Mazdaspeed 3 8th Port Auxiliary Fuel Kit

Ok let’s recap on where the CorkSport Port Injection Kit for Mazdaspeed 3 fits in:

  • 4 Extra Injectors aka 8th Port Fuel Injection Kit – one injector per runner for more precise fueling
  • Return Style Setup – Fuel pressure rising with boost pressure for more capacity and precision
  • Standalone Tank – Cheap pump gas for daily driving and high octane fuel for port injection power in the secondary fuel cell

I don’t know about you, but this sounds like you can have your cake and eat it to!

CORKSPORT MAZDA PERFORMANCE BLOG

Image Credit: Shift Sector Coalinga 2020

Let’s look at the components that make up the CorkSport Port Injection Fuel Kit.  What’s in the Box:

CorkSport Fender Mounted Fuel Cell

This is a huge element of what makes the CorkSport Port Injection Fuel Kit great.  This fuel cell is custom CAD designed specifically for your GEN1 and GEN2 Mazdaspeed 3 to fit hidden under the headlight behind the bumper cover.  At 2.6 gallons capacity you don’t need to refill the fuel cell often and there is an integrated level sensor to remind you when you are at 0.8 gallons.  No in-cab tanks and smells. 

Mazdaspeed 3 Fender Mounted Auxiliary Fuel Cell

Quantum Fuel Pump

  • A 380LPH inline fuel pump is used.  This is a Bosch 044 style pump that has the flow capacity needed and is e85 safe.
Mazdaspeed 3 8th Port Auxiliary Fuel Kit

DeatschWerks Fuel Filters

  • Two fuel filters are used in the system for complete filtration.  A pre-pump 100 micron filter filters the fuel flowing from the tank to the pump, therefore protection the pump from debris.  A post-pump 10 micron filter filters the fuel even more before entering the fuel injectors, therefore protecting the fuel injectors from very small particulates.  Both filters use a dual stage filtration design that incorporates a magnet and a stainless steel mesh media.
Mazdaspeed 3 8th Port Auxiliary Fuel Kit

Spec’d Length 6AN Fuel Lines

  • No headaches and ready to go! Like our Mazdaspeed high pressure fuel line, the included fuel lines are the CorkSport Fuel Lines are spec’d to length and fully assembled ready to use.  The lines are PTFE lined with stainless steel braiding and a hytrel coating for a sleek finish and protection against abrasion.  All fittings minus on 150deg fitting are permanently crimped and sealed.
Mazdaspeed 3 8th Port Auxiliary Fuel Kit

Fuel Pressure Regulator

  • An AEM fuel pressure regulator is used for this return style setup.  This provides easy adjustment and setup of the fuel rail pressure with the included Fuel Lab Analog Pressure Gauge
Mazdaspeed 3 8th Port Auxiliary Fuel Kit

Electronics

  • Too further simplify, a 30amp relay kit is provided.  Relays are a critical component in setting up a port injection fuel system.  This allows you to safely and reliably provide power and control to the fuel pump. With that a Hobbs Switch is also provided, this acts as a trigger for the relay to apply power to the fuel pump when a set boost pressure is met.  Example: when you reach 4psi the Hobbs Switch will signal the relay to apply power to the fuel pump.  This is a great setup for daily driven cars because you only turn on the pump when needed vs running at all times.  It greatly helps the life of your pump.
Mazdaspeed 3 8th Port Auxiliary Fuel Kit

Misc Hardware

  • Lastly is all the misc hardware and brackets to get this into your speed.  We’ve got this handled and clearly show the install process with the online color step-by-step instructions.
Mazdaspeed 3 8th Port Auxiliary Fuel Kit

Alright that’s what’s in the box for the CorkSport Port Injection Kit; now let’s talk about the other required items.  There are 2-3 critical items needed to get your port injection kit up and running.  

Port Injection Controller

  • The OEM ECU and Cobb/Versatuner tuning options cannot control the extra 4x injectors in the kit so you will need a separate controller and software for this.  There is a simple and proven option with the Split Second Additional Injector Controller AIC1.  It comes with a ready to run harness for EV6 injectors and the harness integration for power, signal and control are very simple.  Check it out here and add it to your CorkSport Port Injection Kit for a one stop shop.
Split Second Injector Controller AIC1-V4H EV6 for Auxiliary Fuel System

Injectors

  • You will need 4x injectors for the CorkSport 8th Port Fuel Kit.  The injectors need to have 14mm o-rings top and bottom and the length of 34mm or 48mm (if using the CorkSport intake manifold).  To use with the Split Second Additional Injector Controller AIC1; you will want the EV6 connection style. For capacity we recommend at least 1000cc/mm.  To cover all these requirements just use the Injector Dynamics ID1050x.  They are proven and reliable, you can grab a set right here with the CorkSport Port Injection Kit.
Injector Dynamics 1050x Port Injectors for Auxiliary Fuel System

Bonus!

  • While this is not required for operation, it is highly recommended.  The N2MB Racing WOT Box allows you to change the type of Redline and Launch Control cut to a safer method.  OEM will deactivate the injectors for this vs the WOT Box deactivates the spark plugs.  This is much safer for your engine, especially with running a port injection fuel kit.  With this you can also Flat Foot Shift which is faster and way too much fun. (Insert Fireball Emoji Here)

Why doesn’t the CorkSport Port Injection Fuel Kit include these items? 

That’s a good question and we have a good reason.  Originally the kit was going to, but we asked the community how they would want the kit and the answers surprised us.  A lot of people wanted the kit minus the Controller and the Injectors because they already had those items.  So we pulled those out of the kit as solo items you can choose to add if needed.   

Installing this kit into your Mazdaspeed 3 is a day project with some buddies.  Bank on 6+ hours due to the wiring (its always tedious, but important to do right). Read the installation instructions before starting the install so you are ready with all the needed tools and supplies for wiring. 

Mazdaspeed 3 8th Port Auxiliary Fuel Kit

I do want to note that like any project that involves wiring, there will be some wiring required for the install and the extra wiring and connection you decide you need are not included in the CorkSport kit.  Every car is different and how each person wants to get things wired up is different.  There is also some very minimal drilling required to install the tank mounting brackets. 

CORKSPORT MAZDA PERFORMANCE BLOG

I hope you found this blog helpful and informative not just to learn about the CorkSport Port Injection Fuel Kit, but to also learn about the other setups and options you can choose from.  I hope this helps you decide what is best for your car and goals.  Give us a call if you have any questions, we’d be happy to help. 

Barett @ CS

2 Replies to “Port Injection Fuel Kit for MS3”

  1. there is actually a way to upgrade your disi system to support over 600whp without the need of port or methanol 😅

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