We have love for the Cx5 Turbo

Mazda Cx5 Performance Exhaust

With the success of the CorkSport CX-9 axle back, it was time to turn our attention to the slightly smaller little brother, the CX-5. We are proud to introduce the CorkSport 80mm Axle Back Exhaust for the 2017+ Mazda CX-5 equipped with the 2.5T. If you’re looking for a little more life out of your new CX-5 Turbo, read on for full details on how to give your grocery getter some growl.

Mazda Cx5 Performance Exhaust

With our experience with the SkyActiv 2.5T in the CX-9 and MZ6, we had a pretty good idea of the correct balance of volume and tone that would be a good fit for the CX5-T. With this, we ended up with 80mm, mandrel bent piping that feeds through two large flow-through resonators. The large resonators keep the noise and drone down during regular driving yet the larger piping size and flow through design of the resonators ensures you can actually hear your 2.5T when you get on the gas. It’s a throaty and deep sound that adds some much needed excitement to the CX-5. Its not all sound though, the larger piping and flow through resonators are much less restrictive than the OEM muffler section. While we haven’t had a chance to get a CX-5 on the dyno, the 2.5T is definitely breathing easier.

80mm Cx5 Turbo Exhaust System

Aside from the obvious sound benefit, the CS axle back adds a visual boost that looks at home on the rear of the CX-5. The exhaust tips were enlarged to 100mm to fill in the bumper cutouts. They were also extended outward slightly, and a slant cut was added to the end. This gives a stylish and classy look that should’ve been the way Mazda made it! The tips are garnished with a laser engraved CorkSport name badge for a nice finishing touch.

Tig Welded Mazda Cx5 2.5T Exhaust

The entire CorkSport exhaust is made from fully polished 304 stainless steel that is precision TIG welded together. This construction ensures good corrosion resistance and strength to last as long as you own your CX-5. Plus, being fully polished, it looks great if you ever catch a glimpse past the tips. In addition, we supply the hardware and gaskets you need for installation, so spicing up your CX-5 can be done in as little as 30 minutes!

Want to hear the Cx5 Turbo Exhaust? Check out the Youtube Vid below..

Cx5 Turbo Performance Dual Exhaust

There you have it, the new CorkSport 80mm Axle Back for 2017+ Mazda CX-5 2.5T. Be sure to visit HERE for sound clips and video of the exhaust on car!

For all you 2017+ non turbo Cx5 owners, yes this will fit your Cx5. The exhaust note of the axle back will be different without the turbo in the system and will be comparable to our 1st Gen Cx5 axle back.

If you’re still curious, give us a call and we can answer any question you may have!

2018+ Mazda6 Performance Exhaust for the 2018-up 2.5T

Mazda did a great job bringing a turbocharged engine back to the Mazda 6 (Mazda 3 next please?), but may have done too good of a job of keeping it quiet. Say hello to the CorkSport 80mm Cat Back Exhaust and Axle Back Exhaust for 2018+ Mazda6 equipped with the turbocharged 2.5L engine. If you’re interested in waking up your SkyActiv-T in both excitement and power, read on as we breakdown the newest CS exhaust.

As with all CorkSport exhausts, the goal of the MZ6 2.5T exhaust is to improve power and sound by improving the flow of the OEM exhaust. We started by increasing the size of the piping from 60mm to 80mm. That is an increase of over three-quarters of an inch to really help your turbocharger breathe better. In addition, the CS exhaust system eliminates the crushed areas present in the OEM exhaust and replaces the restrictive muffler sections with pass-through resonators. These resonators control volume and drone without affecting power output.

All that extra flow does mean a power increase. In our in-house dyno testing, we saw an increase in 5-6WHP just by bolting on the CorkSport  Cat Back Exhaust. Check out the dyno sheet down below to see. This increase came with no tuning changes, no check engine lights, and the only other mod being the CorkSport Short Ram Intake, which was installed for both tests. With the 80mm piping size, this exhaust is ready to support future modifications and would likely show more power gains with proper tuning.

The CorkSport MZ6T exhaust is more than just function. We went through multiple iterations and designs to ensure the best sounding exhaust for your 6. The finished product ups the volume without being annoying to daily drive yet still sounds great when in hard acceleration. We strongly recommend you watch the video below to hear what to expect from this exhaust.

If you feel the video below gives you too much volume for the daily, then check out the Axle Back Only Exhaust.  Recently added to the CorkSport line-up, the Axle Back alone adds a mellower, but still noticeable tone to the exhaust.  This is a great middle ground between the CorkSport Cat Back and the stock exhaust.

To give a great looking, long-lasting finish to each exhaust, they are manufactured from fully polished 304 stainless steel. To ensure a high quality fitment, all components are precision TIG welded together on jigs made from OEM exhaust components. Lastly as a finishing touch, we use 100mm dual wall exhaust tips. They fill out the bumper cutouts and are extended slightly to give a classy look and enhance the new Mazda 6’s styling.

The CS Mazda 6 Turbo Exhaust comes with all the hardware and gaskets you need for installation, high quality instructions, and CorkSport support for any questions you may have. Pick up a CorkSport MZ6 2.5T Exhaust today and liven up that daily commute.

CorkSport CST6

Testing & Validation of the CorkSport CST6

As we get closer and closer to announcing the launch of the new CorkSport Turbo Line-Up we want to share the testing and validation we put our turbos through.  You may not realize it, but we’ve already shared a lot about the CST6 without really saying so, check out Barett’s Built Gen1 Here.  

So we’ve talked a bit about the design intent behind the CST6; defining the wheel sizes, wheel size ratio, and the ball bearing CHRA.   If you’ve seen the teaser listing then you’ve already seen the 633 whp dyno graph, so we’ll look at the data to support it!

The First Look at the CST6 Performance

CorkSport CST6 dyno at 28psi
CST6 running at 28PSI

First let’s look at the CST6 at a more moderate boost pressure.  Above are the results of back-to-back testing comparing the XS-Power V3 Exhaust Manifold and the upcoming CorkSport Cast Exhaust Manifold.  All dyno runs were performed with the same 28 psi peak pressure tune.

So the exhaust manifold testing is exciting, but it’s not what we’re here to discuss.   What I want you to know is that the CST6 is fully capable of providing mid-500 whp power at 28 psi.   While we have and will continue to push the CST6 to its max ability, the 27-30 psi range has proven to be a sweet and efficient spot for the CST6.

Testing the Limits on the CST6

CorkSport CST6 Dyno Graph running 34psi
CST6 running at 34PSI

Searching for the limits with the current fuel system we can easily push past the 600 whp mark plus some.   The efficiency of the CST6 at this power level is still very strong and the turbo continues to pull through the RPM range.   What really makes the CST6 shine is the power under the curve. This is a BIG turbo and will respond like one, but the loss of early spool is easily compensated for with the abundant power curve and power that carries past 7500 rpm.  

It’s important to note that testing for the CST6 is not finished because we are currently limited by the fuel system on the vehicle.   The current fuel system is OE DI injectors paired with a boost based methanol system flowing 40 gph peak. In the near future, we will continue finding the limits of the CST6 with a true port injection system and Split-Second controller flowing E85.   This will give us headroom for 8000+ rpm and boost levels past 34 psi (let’s see what 40 psi give us!).

Looking at the CST6 Data Log

CorkSport CST6 Data Log
MAF Voltage and Actual AFR of the CST6

This is a datalog form the 633 whp dyno run and was recorded on the chassis dyno.   Because of that, it is not a perfect example of street driving… let me explain why. The dyno dynamics chassis CorkSport uses can control load and thus the rate at which the engine can rev through the RPM range.   In order for us to dyno a vehicle at this power level safely, we need to find the right ramp rate for low RPM and high RPM. The biggest factor this affects is the spool RPM of the turbo.

On the graph I marked ~200 rpm shifted to the left for the boost curve.   On the street, the CST6 spools about 200 rpm sooner due to the higher load on the street vs the dyno.   This puts the CST6 @ 20 psi around 3800-3900 rpm.

Also shown on the graph are MAF voltage and actual AFR.   Both of these are important because they provide real data about how the vehicle is being tuned.

Target AFR is set for 11.76 which is neither rich nor aggressive for this setup.  The slight up and down of the AFR curve from 3500-4000 rpm is due to the very high amount of auxiliary methanol starting to spray along with the DI injectors.

Looking at MAF voltage you can see us get well past 4.50v.  Actually, we are consistently seeing MAF Voltage around 4.65-4.70v using the CorkSport 3.5” Intake which has a true ID of 3.50”.  This is just further validation that the CST6 is flowing enough air to support 600+ whp.

There’s more to come from the new CorkSport turbo lineup so stay tuned for more info on the CST5, CST6, and EWG housings.

-Barett @ CorkSport

CorkSport External Wastegate Housings: Design and Product Details

During our development of the new CST6, it became clear that an external wastegate (EWG) would be the only option for optimum performance and boost control — Read about the CST6 design here. Since we were already developing a housing for this turbo, we just HAD to make similar options for both the tried and true CST4 and the upcoming CST5. In today’s blog we will cover what makes the new CorkSport EWG Housings tick and go through how the systems are different from a typical internal wastegate (IWG)setup.

CorkSport External Wastegate for Mazdaspeed
Mazdaspeed External Wastegate Housing.

How The CorkSport EWG Housing Works

Starting with the basics, the CorkSport EWG housings replace the turbine or “hot” side of your CST4 or CST5 turbocharger. The CS housings eliminate the small “flapper valve” of the internal wastegate with a path to a standalone wastegate actuator. While the housings will not come with the actuator itself, they will include everything you need to mount up a Tial 44mm (or equivalent) EWG, with the option to grab a screamer pipe to go with it.

CorkSport MazdaSpeed3 external wastegate
Mazdaspeed 3 external wastegate.

EWG Housing Placement

The placement of an external wastegate is very important for proper boost control. We chose the location of it carefully as the offshoot from the scroll of the turbine provides an optimum path into the wastegate. As shown in the diagram below, a shallow angle into the wastegate offers the best exhaust flow path which results in optimum boost control.

Wastegate Placement Diagram
Mazdaspeed wastegate placement diagram.
Click to Expand

A Properly Sized Wastegate

Sizing is also important for boost control. Too large of a wastegate is hard to fit on the car and can be difficult to control boost as it does not need to open much to flow a lot of volume. Too small of a wastegate can cause over boosting from a lack of flow. For most Mazdaspeed applications, 38mm and 44mm sized wastegates are most commonly used. We chose the 44mm option for its better usability on the street. Since a street car is not using the turbocharger at peak efficiency 24/7 and is usually at a relatively low boost level, the larger 44mm wastegate will more effectively vent the excess exhaust gases.

EWG Tial for Mazdaspeed 6
External Wastegate Tial for Mazdaspeed 6.

Choosing An Internal or An External Waste Gate

Now on to a big question: why an external setup over and internal setup? While they both have their pros and cons, the biggest answer is better boost control. In general, an external wastegate setup will control boost more accurately and respond quicker to changes in boost than an internal one. While the CST4 and CST5 have been optimized to work with IWG, an EWG setup will almost always have better boost control. It should be noted that, generally speaking, an EWG will have higher peak power capabilities. First, back pressure in the exhaust system is reduced due to the removal of the exhaust gas that would usually cause turbulence as it exited the IWG right near the turbine exit. Second, an IWG setup can reach a limit in flow where literally no more gas can flow through the turbine & IWG port. Most EWG setups do not have this problem as the EWG port can be larger & the wastegate gases do not have to exit in the same location as the turbine gases.

Check out the diagram below, as it illustrates a common problem with internal wastegate setups. A boost spike as desired pressure is achieved then inconsistent boost as RPM increases. External setups (right diagram) typically do not have either of these issues and can achieve a near flat boost curve.

Internal and External Wastegate performance chart
(Left) Internal Wastegate Setup | Common Issues
(Right) External Wastegate Setup | Optimized Setup
Click to Expand

The CorkSport External Wastegate Design

Moving to an EWG design allowed us to tweak the design of the housing itself. The CorkSport external wastegate housings all use a ~0.82 A/R. This number is a ratio that is determined by the geometry of the scroll. I won’t go too much into it, but for more info be sure to check out Barett’s turbocharger white paper here. This is larger than the CorkSport internal wastegate setups. Essentially, the increase means you may sacrifice a little bit of spool time but gain peak power capabilities at high RPM.

In addition, the volume of the scroll itself was increased. This is referred to as “swallowing capacity”. By increasing this volume, the turbine housing will be able to air more efficiently at peak, again increasing your max power potential. This is especially important when you have a high flowing ported head or an upgraded exhaust manifold. Check out the CAD models below, you can really see the difference in the scroll size.

CorkSport Turbine Housing
CorkSport Turbine Housing for Mazdaspeed 3.

I almost forgot the best part! An external wastegate setup gives you the option to run a screamer pipe which sounds amazing while under boost. While screamer pipes are sold for race use only, they add far more excitement to a wide open throttle pull! Stay tuned for more, next time we will be sharing testing information & some more teaser shots.

-Daniel @ CorkSport

New & Improved: The CorkSport Aluminum Skid Plates for Mazdaspeed 3

CorkSport Aluminum Skid Plate
CorkSport Aluminum Skid Plate

Aluminum Skid Plates for 2008-2013 Mazdaspeed 3 and 2004-2013 Mazda 3.

While not a new product, there is still plenty to be excited about. Say hello to the new and improved CorkSport Aluminum Skid Plates for 2008-2013 Mazdaspeed 3 and 2004-2013 Mazda 3. We took all of the great features present in the original one-piece design, and then went back to the drawing board to improve the fitment, make installation easier, and make shipping cheaper for everyone. Read on as we go through the full details of this redesign.

CorkSport MazdaSpeed 3 Skid Tray
GEN 1 Skid Plate for 204-2009 Mazda 3.

Designing the GEN 3 Skid Plate

While designing the GEN 3 Skid Plate for 2014-2016 Mazda 3, we realized that utilizing a two-piece design is a fantastic way to save you some money on shipping. The overall design is smaller which allows us to use a smaller box to eliminate any oversized package charges from shipping companies. This is the same reason why our GEN2 Speed3 Front Lip is made of multiple parts. By designing the skid plate into two-pieces, installation on your vehicle becomes more flexible when aligning the front and rear sections. The multi-piece lineup creates wiggle room to help get everything all lined up properly on your car. Since each and every car is just a bit different, the extra wiggle room helps to achieve the best alignment possible, even on cars that have had their subframe, radiator support, and/or bumper removed and not reinstalled perfectly.

CorkSport Skid Plate for MazdaSpeed 3
Skid Plate for 2010-2013 Mazda 3 and Mazdaspeed 3

The Perfect Fitment

Going to a new design gave us the freedom to improve fitment even further. We have revised the mounting locations to ensure the easiest installation possible and reshaped a few areas to best fit on your car. Like the original though, no permanent modification to your Mazda is needed as we use all OEM mounting locations. Plus, the CorkSport Aluminum Skid Plates for Mazdaspeed 3 ship with all of the tools that you will need to install it.

CorkSport Underbody Skid Plate
CorkSport Underbody Skid Plate for MazdaSpeed 3

Ultimate Protection Without the Weight

Both GEN1 and GEN2 CorkSport skid plates are made from laser cut and precision formed 0.090” aluminum sheet. This thickness offers great protection from road debris and the occasional tall speed bump without adding a ton of weight to the front of your Mazda3. Where an OEM plastic splash shield would crack and fail, the CorkSport skidplate can take a beating, offering you peace of mind whether you’re riding at stock height or have lowered your MazdaSpeed 3. Speaking of riding low, the CS under tray sits up slightly higher than the OEM shield, giving you that little bit of extra clearance when you need it.

CorkSport Aluminum Skid Plate Installed
CorkSport Aluminum Skid Plate on MazdaSpeed 3

If this is just your next mod in a long list of mods do not worry. The CorkSport Aluminum Skid Plates fit with both GEN 1 and GEN 2 Front Mount Intercooler Kits as well as the CorkSport Lower Tie Bar. The CS GEN2 Front Lip will fit as well but may require some modification to the skid plate and/or front lip. For all of you Mazda 3 owners, just a heads up that these skid plates were designed for the Mazdaspeed models so you may require some minor trimming for best fitment, all of which can be done with a simple hand saw or razor knife.

CorkSport Aluminum Skid Plate

There you have it folks, the new and improved CorkSport Aluminum Skid Plates for GEN1 and GEN2 Mazdaspeed 3 & Mazda 3. Let us know if you have any questions down below and we will be sure to help you out!