Turbo Mazda 3 Guide!
Foreword: This brief article is a culmination of knowledge and experience from the entire team at DRTuned Racing, members of the ‘Boosted Mazda L-series (1.8 / 2.0 / 2.3 / 2.5) Motors Owners Group’ on Facebook, and especially Nate Spangler for putting together an initial guide that summarizes much of this information from his own experiences.
So you want a turbo?
You’ve either installed all the bolt-on parts available and you still want more, or you know that 200hp isn’t enough for what you want to accomplish. Your first question is probably “How much power can I make?”, or “How much boost can I run?!”. The answer, as with most things, is that it depends. And what it depends on, are the following questions and topics that we will discuss on how to turbo a Mazda 3!
What’s your budget?
Before we can begin talking about what turbo to use, how much power you can make, or what colour air filter you should get… You need to figure out the money. There are a lot of costs involved in installing a turbo kit on your Mazda 3, some you can avoid or reduce, and others you simply cannot. A typical starting point for entry turbo builds is around $5,000. It can certainly be done for less, however that will require all work to be done yourself, and a lot of resourcefulness to put everything together. ALWAYS budget more than the anticipated cost. This is a fairly complex task, and you will run into unexpected issues and expenses that can possibly leave you with a 3,000lb paper weight if your funding has run dry.
Certain parts require quality, while others can be generic from eBay, you may be able to perform all the work and any fabrication yourself, but if not then those are additional costs. Chances are your local shop isn’t very familiar with the platform, and they will be charging top dollar for custom one-off jobs such as this. While you may find plenty of information online about turbo kits, or find companies that still list turbo kits for sale, the fact is that there are none available to be purchased. You will be piecing your entire build together yourself, or filling in the gaps if you can find a used turbo kit for sale.
Tuning is the single most expensive and most important piece of the budget and entire process. Your local tuning shop will not be able to tune the factory ECU on the Mazda 3 to handle a turbo. Our Turbo Tuning Kit includes everything needed to properly tune your new turbo Mazda 3, wherever you are in the world!
Where does that money get you?
Once you’ve established a firm budget, we can begin to look at what modifications and power levels you’ll be able to afford and sustain. Big power takes big money, and once you reach the limits of your factory engine internals an engine build will be required. Good power level can however still be achieved with the stock engine internals. The Mazda 3 2.0L and 2.3L engines can both handle around 250-270hp safely without any internal upgrades. The 2.5L has been known to handle horsepower near 400hp, though a breaking point has yet to be determined. An entry build with 220-270hp is doable with the aforementioned $5,000 budget.
To build or not to build?
Forged internals aren't necessary until you're aiming for over 10psi or so of boost, assuming you've got a manual transmission. For a first time build it's just simply not recommended. Put together a good reliable kit that can handle 8-9psi consistently and run that for a while.
Once you work out all the quirks of running a turbo then you can consider building a second motor and getting the bigger injectors, bigger turbo, etc while your Mazda 3 is still drivable and still running fine.
There are too many moving parts if you try to go for a big build initially. You will learn a lot from your first build, makes mistakes, change your mind etc and want to change it in the future, so don't make your first build a big expensive one.
Lets consider getting this extra power on the ground.
First and foremost is your transmission. The automatic transmission is the weakest link, and will limit power to around 220-230hp. The 5spd manual transmission is far more stout, and is capable of handling around 300hp or just in excess of what stock internals can withstand. A transmission swap is entirely possible, and a few have been done successfully, but it is not a simple task and not recommended as a first move. Your suspension, tires, motor mounts, and brakes will all need to be considered and possibly upgraded or replaced if they are not up for the task of an added 50-100hp. It’s important that all components be properly maintained and well kept to minimize the risk of breaking parts and stressing other components.
So how do we tune this thing? With DRTuned Racing Of Course!
Tuning solutions of the past have included piggy back ECU's and electronic controllers, fully standalone aftermarket ECU's, and OEM ECU re-flashing if it could be found. The piggy back and standalone solutions leave a lot to be desired by trying to mimic what manufacturers developed over many years in a matter of days.
The simplest, and by far most cost effective way to tune your custom turbo Mazda 3 is to purchase our Turbo Tuning Kit! This kit includes everything needed to re-flash your factory ECU using our Remote Tuning service.
By re-flashing your OEM ECU with our custom turbo tuning, we are able to retain all of the factory development and refinement while still compensating for the appropriate fuel ratios and ignition timing that is needed for your turbo Mazda 3.
Finally! Lets talk turbos.
There are several options for turbo chargers, and ultimately it will depend on your short and long term goals. If you think you’ll be satisfied with the power levels a stock motor can provide, then there’s no need to buy a turbo, injectors etc that will handle power any higher than those limits. The stock Mazdaspeed turbo, Borg Warner K04, is a well balanced turbo for this range of power. It offers quick spool, good flow characteristics up to traditional RPM limits, and are very affordable and easy to find. The Mitsubishi TD04 is a very similar size, capable of putting out upwards of 300hp worth of flow, and can be found in a variety of flange types to suit your needs. The Garret GT28 size is capable of a fast OEM like turbo spool, and is also able to put out significant power levels if you decide to build your motor in the future, or have a 2.5L engine that requires a larger turbo and can handle much higher horsepower from the factory. We would not recommend going larger than the GT28 for a first time build, as the costs and difficulty of build requirements increase with larger turbo’s and higher horsepower levels.
NOTE: The 2.5L engine will spool smaller turbo's far too quickly!! Anything smaller than a GT28 size turbo is not advised for a 2.5L build. However, K04's have been successfully used in the past, high quality and well planned boost management are the key.
So what parts do you need?
Below is a very brief general outline of the necessities and requirements to get started. As mentioned, some components can be sourced universally, and others MUST be high quality and/or genuine in manufacturer.
- Exhaust Header
- Wastegate/Wastegate Actuator
- Intake Manifold (varies)
- Boost Controller
- Upgraded Manifold Pressure Sensor (varies)
- Oil Feed Line
- Oil Return Line
- Intercooler Piping
- Turbo Inlet/Intake
- Blow-off Valve or By-pass Valve
- Gauges (Boost, AFR, Oil Pressure)
- Spark Plugs
- Coolant Lines for turbo (varies)
- Fuel Pump (varies)
- Catch-Can (optional)