Mazdaspeed Turbo – Choose Your Boost

May of 2015, CorkSport launched its first high performance drop-in turbocharger for the Mazdaspeed platform.  Fast-forward almost 4 years and CorkSport again is about to redefine what a stock flange turbocharger for the Mazdaspeed platform can truly be.  

The original “CS Turbo” is now the CST4 to follow the turbo line-up that is soon to launch.  The CST4 took a fresh approach to “big turbo” with all the included hardware, gaskets, and of course direct drop-in fitment.  It removed the guess work for a quick and easy installation, but the benefits didn’t stop there. This “little big turbo” packs a punch for its compact TD05H-18G wheels.  

With the CST5 and CST6 just around the horizon it would be easy to forget about the tried and true CST4, but don’t worry this Mazdaspeed Drop-In Turbo got some new love also.  You will now have a EWG housing option for the CST4. You can pick it up in EWG setup from the start or if you already have a CST4 that you love, you can get the EWG housing kit to do the upgrade yourself.

Moving onto the CST5 & CST6 the possibilities for the MZR DISI have moved up significantly.  What started as a single “bigger big turbo” has morphed into two “bigger big turbos” that, we feel, better provide for the various power goals of the community.  

We present to you the CST5

The CST5 bridges the gap between drop-in performance and big turbo power.  The journal bearing CHRA uses a hybrid TF06-GTX71 wheel setup that provides more top-end than the CST4 with minimal spool and response penalty.  Upping the big turbo feel is a 4in anti-surge compressor inlet which will require an up-sized intake system.

Unlike the CST6, the CST5 will be offered in both internally waste-gated and externally waste-gated setups.  This provides you with the flexibility to setup your Mazdaspeed just how you see fit and both have been proven 520+whp on our in-house dyno and tuning courtesy of Will Dawson @ Purple Drank Tuning.

Now… We present to you the Stock Flange Record holder…the CST6

Image: Mazdaspeed-6-big-turbo

The CST6 redefines what the community thought was possible from the stock turbine housing flange, but first some details.  The ceramic ball bearing CHRA uses a GTX3576r wheel setup that clearly out powers the CST4 & CST5, but that’s point remember?  

The CST6 is a legit big turbo, spool will be later, but still sub 3900rpm for full boost, however a turbo setup like the CST6 is not intended for low-end response.  If top-end power is your goal, the CST6 will deliver. In-house testing has pushed the CST6 to 633whp at a fuel limited ~33psi and 7900rpm redline.

Unlike the CST4 & CST5, the CST6 will only be offered in EWG setup.

In the coming months, we will be sharing more information about the CorkSport Turbo Line-Up; the design, the testing, and validation of each.  For more information about the CST5 & CST6 along with the new EWG turbine housing option, check out these sneak peek pages.  

Thanks for tuning in with CorkSport Mazda Performance.

-Barett @ CS

MZR DISI Injector Seals – The Correct Seal for YOUR Speed

Many years ago we helped bring a revolutionary design to the Mazdaspeed community.  Fast forward 4+ years and you’ll find that the CorkSport Tokay Injector Seals are still the best option for your Mazdaspeed.  

Recently, we had a customer ship their stock block engine core to us for a fresh Dankai 2 Built Block.  During the engine core tear-down and inspection, we found a set of CorkSport Injector Seals installed.  We realized this was a great opportunity to share what we found with the community.

When the CorkSport Injector Seals arrive at your door they look like this:

Brand new a fresh of the lathe with all of their beryllium copper brilliance.  After many thousands of miles of use and abuse they look like this:

Now to the untrained eye you may think they look bad, but the truth is they look fantastic!  The visible top of the seal has a small amount of carbon deposits present. This is to be expected because this surface is exposed to the combustion chamber.  Moving to the side of the seal you can see a distinct clean edge and no carbon deposits on the sides of the seal. This distinct clean edge is where the exterior of the seal is designed to seal in the cylinder head.  This is awesome!

Now let’s look at the inside of the used seals:

Again we see carbon deposits, but they are in and only in the expected locations.  Moving up the side of the seal you can see a “shelf” or “step” that is clean. This is the edge that the fuel injector seals against. Beyond that the inside of the seal is clean.

From this inspection we can see that the injector seal was functioning as designed and doing its job effectively.  

So you might be asking…”What is so special about this design?” Well, we wrote a two-part design blog answering that exactly.  We highly suggest spending the 10 minutes to read these.

Injector Seals Design Part 1

Injector Seals Design Part 2

This is exactly why every single CorkSport Dankai Built Long Block includes a set of CS Injector Seals, but if you’re not looking for a built block but still want the assurance of the CS Seals you can check them out right here.  The install of the seal can be a bit tricky sometimes, especially getting dirty injectors out of the cylinder head.  Because of that we’ve developed an injector puller tool that makes the job MUCH easier.  

We hope you enjoyed this quick tech inspection of the injector seals!  Thanks for tuning in with CorkSport Mazda Performance.

-Barett @ CS

The CorkSport EGR Delete Kit is Here!

If you’re looking to help your racing engine stay healthy and clean, read on as we introduce the CorkSport EGR Delete Kit for Mazdaspeed 3, 6, and Mazda CX-7 Turbo.

An exhaust gas recirculation (EGR) system is a very common control system that recirculates some exhaust gases back to the intake manifold to help reduce NOx emissions. A properly functioning system has a few other minor benefits however, on the DISI MZR the EGR system primarily gets clogged,  and/or gums up your intake valves, reducing engine health and performance (for more info, check out our blogs on EGR Cleaning and Intake Valve Cleaning).

The CorkSport EGR Delete Kit removes the two primary components in the EGR system: the EGR valve and the EGR tube. This means no more carbon and soot going into your intake valves, and when coupled with a quality Oil Catch Can, much less frequent valve cleaning.

Each CS EGR delete kit comes with everything you need for a good looking, easy install. The EGR valve is replaced with a 3/8” thick, billet aluminum block off plate. The plates are precision machined to closely match the OEM EGR valve flange to keep your install clean. Proper length bolts are supplied with the CS EGR Delete Kit to ensure you won’t damage your OEM or CS High Pressure Fuel Line.

The EGR tube delete consists of two components: a laser cut 18 gauge T304 stainless steel block off plate and a T304 stainless plug. The plate can be used underneath the tube itself for a stealth install or for an even cleaner engine bay, go for the full tube delete and use the plug to block the hole in your OEM intake manifold.

While not a typical performance mod, the EGR delete is a great addition to aid in a racing build’s future mods. To start, the EGR valve block off plate is tapped for the included 1/8”-27 NPT barb fitting. This works great for the OEM turbo’s rubber coolant line, but should you upgrade to a non-water cooled turbo or a stainless coolant line, 1/8” NPT is a very common size that should be able to accommodate almost any type of fitting.

The CorkSport EGR Delete Kit also provides some much needed room around the turbo charger. With the bulky OEM EGR valve removed turbo swaps are easier, plus, certain turbo setups will literally not fit without an EGR delete. Finally, should you decide down the road to upgrade your Intake Manifold, an EGR delete is basically a must as nearly all aftermarket intake manifolds remove the EGR port from the IM.

The CorkSport EGR Delete Kit is a relatively easy way to gain some extra engine protection without breaking the bank. If you just cleaned your valves and want to avoid it doing it for a long time, a CS EGR Delete Kit is a must.

An Inside Look at the CorkSport EBCS

We recently came across one of the original CorkSport EBCS prototypes which gave us a perfect opportunity to break it down and give you all an in-depth look. Read on as I go through what makes the CS EBCS tick, and more importantly how it gives you great boost control on your Mazdaspeed.

Just as a refresher before we dive in, an electronic boost control solenoid (EBCS) allows for precise boost control by using an electric solenoid to help control the wastegate. A boost reference travels to the EBCS where it can either push on the wastegate diaphragm or vent to the turbo inlet pipe. Where the air travels is controlled by the solenoid.

Obviously, the specifics change slightly depending on a number of factors with the turbocharger setup, but the concepts remain similar. Since the solenoid is electronic, it can be controlled within a tune. This means you are not wholly controlling your maximum boost with the spring in the wastegate and can hit boost targets larger than the “10psi” spring in your wastegate. For more information on boost control and the different EBCS setups, checkout Barett’s white paper on the subject.

Now the above image is a little different from the way you are usually seeing the CS EBCS. Not only is it missing the sweet black anodized finish (early prototype remember?), it needs some assembly before it can function properly. Below lists the components in the system and a short description of what they do. Obviously, we are missing a few key o-rings to keep everything nice and sealed, but all the important bits are there.

  • Manifold: This is the air distribution block. Air/boost comes in one port and leaves through a different port. Where the air goes is determined by the bullet valve.

  • Bullet Valve Assembly: More on this later, but essentially the center rod (piston) moves in and out while the black portion prevents air from reaching one of the manifold ports as needed.

  • Tension Spring: Keeps the bullet valve in the correct position when the system is not energized.

  • Coil Seat: Ensures the copper coil stays in place so the valve can operate properly.

  • Coil/Windings: Creates a magnetic field when energized that moves center rod of bullet valve.

  • Solenoid Body & Wiring: Contains the coil and other components. Also attaches the valve to the manifold.

Each one of the “thirds” of the bullet valve corresponds to one port on the EBCS manifold. They are labeled accordingly above. As EBCS is energized, the piston of the valve is pulled by the magnetic field created by the windings. There is a small amount of movement; only about 12 thousandths of an inch (0.012”) to be exact, which is enough to allow air to either reach the wastegate diaphragm or pass by into the turbo inlet pipe. Again this is simplified as it does not touch on duty cycle-the valve is typically rapidly opening and closing (seriously, check out the white paper).

The bullet valve is advanced technology that offers the utmost in fast responding fluid control. In addition, its profile offers the ability to make a pressure balanced valve and have a manifold that fits just about anywhere. All of this tech means you end up making boost faster, minimizing boost spikes, and keeping boost creep in check. If you want the best in boost control for your Mazdaspeed, be sure to pick up a CorkSport EBCS.

2010 MS3 – Best Way to Get 40+ HP

Your Mazda breathes just like you do. Maximizing the intake of air for your Mazdaspeed and freeing up the expulsion of used gasses (exhaust) will help your vehicle breath better, and go faster.

On the intake side of things, you can set yourself up with a Stage II Power Series Short Ram Intake which includes our mandrel bent turbo inlet pipe, custom designed MAF housing, and silicone coupler. This will free-up flow into the stock turbo and allow your Mazdaspeed to breath deeper. The average gains seen here are 10-15 hp.

For exhaling, you want your Mazdaspeed3 to expel all those used gasses as quick as possible. With the CorkSport turbo-back exhaust, you are reducing the back-pressure and allowing your Mazdaspeed to utilize the potential of its turbo. The kit comes with CorkSport’s full 80mm catback dual exhaust, racepipe, and downpipe. This setup will give the average MS3 owner 28-31 hp at the wheels.

Shown below is our 2010 Mazdaspeed 3 with the CorkSport Short Ram Intake & Turbo-back exhaust and stock turbo, compared to the same Mazdaspeed3 completely stock. The before number is 226 hp and came out to 272 with the SRI and Turbo-back exhaust. That is a 46 hp increase to the wheels with two products.


For those of you on more of a budget, may I suggest just the Short Ram Intake and racepipe? For this smaller investment, you can get an increase of wheel hp in upper 20’s to lower 30’s.