Mazda’s Dynamic Pressure Turbo – A Closer Look

There has been a lot of buzz about the new(ish) turbocharged SkyActiv-G 2.5L first found in the Mazda CX-9 and now in the Mazda 6.  Along with all this buzz, there are a lot of unknowns as well. Here at CorkSport, we’ve taken the step to try and address some of these unknowns.  What is Mazda’s “Dynamic Pressure Turbo” and how does it work? There have been diagrams bouncing around on the internet, but no close-up view of the turbocharger itself.  That’s about to change.

If you haven’t already read Daniel’s first installment, “Mazda Dynamic PressureTurbo an Introduction.” You wouldn’t want to miss out on the extra information before reading on.

The turbocharger found in the 2.5T equipped CX-9 and 6 is quite complex in design.  There are many aspects to the OE turbocharger we could discuss, but today we are going to focus solely on the dynamic pressure system and turbine housing.  

If you are reading this, then you’ve probably already seen various diagrams depicting how the dynamic pressure system works and showing Mazda’s clever 3-2-1 exhaust port design.  If you haven’t, check it out below.  Image credit to Car And Driver Magazine for the fantastic diagram.  

Mazda’s 3-2-1 exhaust port design takes full advantage of the engine cylinder firing order.  The advantage is improved exhaust gas scavenging for the adjacent cylinder (more or less the cylinder that just fired helps pull the exhaust gases out of the next cylinder that is about to fire).  Ok moving on; this is great, but how does the dynamic pressure system come into the mix?

Shown here are the turbocharger assembly and the dynamic pressure valve assembled as one unit (the first two images also showed the fully assembled setup).  The three ports are clearly visible along with the “vane” that passes through the three ports. This vane rotates depending on engine RPM to control the exhaust gas velocity entering the turbine housing.  The vane itself is controlled by the larger blue colored actuator.

Now let’s take an even closer look.  The vane does not open until approximately 1600rpm, but the engine could not run of no exhaust gas can flow out of the engine.  To resolve this Mazda has designed the dynamic pressure system with two exhaust gas paths.  Looking at the above image you can see a small opening just above the vane. This is the sub-1600rpm exhaust gas path.  

By reducing the cross-sectional area of the exhaust gas path, the exhaust is forced to accelerate through the dynamic pressure system and into the turbine wheel.  This effectively reduces turbo lag, improving the vehicle’s response at low engine RPM. Once the engine revs past 1600rpm the vane opens, allowing the larger path to be used.   

Here we show the turbocharger assembly (right) and the dynamic pressure valve assembly (left) separated.  Looking at the dynamic pressure valve assembly, you can now more clearly see the three small paths above the larger path with the vane inside.  Then look at the turbocharger assembly and you will see the small upper path and the larger lower path.

The fact that these two assemblies are separate systems is great news for the enthusiast.  The development of a performance turbocharger will be much more feasible and the dynamic pressure valve can be retained with the performance turbocharger.  One more detail to point out.

Mazda put a lot of thought into the design of the wastegate port; let me show you why.  First, looking at the inlet of the turbine housing you can see a small vertical wall in the large path.  This wall creates a completely separate path to the wastegate port which is very unusual on an OE turbocharger. Combine this design with a very large wastegate port and you get a design that can “waste” or divert an excessive amount of exhaust gas.

This tells us the SkyActiv-G 2.5L engine is creating a lot of (currently) unused exhaust gas energy.  Again this supports the feasibility of a performance turbocharger suiting Mazda’s new turbo engine quite well.  

Great things are on the horizon for the 6, now if only Mazda would put this engine in the 3 paired with a 6-speed manual transmission.  Oh, one can dream.

-Barett @ CS

All About That CatBack Exhaust

Mazda Catback Exhaust Installed

Ever wondered the key factors of making a decision about your aftermarket exhaust? Why Cat-back? 

Is it the diameter of the exhaust that says performance? Or is it the type of metal used? What about fitment to your current setup? None of these questions by themselves answer what you need by themselves, but all of them together help when making the decision on how to get more power out of your Mazda.

At CorkSport, we have made it our #1 priority to make our customers dreams a reality. Whether you drive a Mazdaspeed or a regular Mazda, we’ve made sure to engineer a great fitting exhaust that maximizes engine performance.

Check out the Cat-Back Exhausts by Car Model Below:

Take the Mazdaspeed 3 for example: When you purchase a CorkSport Catback Exhaust, you’re getting T304 stainless steel piping that has been polished to a mirror-like finish.

You’re also getting true 80mm piping, which is slightly bigger than three inches, making our exhaust one of the biggest bolt on catback systems.

Fitment is also a big concern to us. We make sure our exhaust systems are mandrel bent and TIG welded to make a perfect bolt-on fitment.

Mazda 6 Power Series Exhaust

Now that you know our exhaust is 80mm piping, polished to perfection, and made to be a direct fitment, you can bet this exhaust will increase performance and sound. By installing our cat-back exhaust, you’re removing the secondary unmonitored catalyst making the exhaust flow much faster out of the motor. By increasing the velocity of exhaust gases out of the motor, you increase power and make your turbo spool up a little bit faster.

Among the power gains you’ll see from installing the CorkSport Catback Exhaust, you’ll also have a car with a deep growl to it. Our exhaust has one of the best sounding tones on the market. With a quality made exhaust, comes quality sound.

When find yourself ready for a cat-back exhaust, be sure to check out CorkSport to ensure you get the highest quality for your ride.

 

2018 Mazda 6 Performance Parts – Cold Side Boost Tube

You have probably heard us mention the new Turbocharger Mazda 6 in the recent weeks and months and have probably been wondering; “what’s going on?”  Well, today we’d like to share a little bit about what’s been going on at CorkSport HQ with our very own 2018 Mazda 6.

Right off the bat, I can say we have a handful of exciting performance products in the works and will be sharing info on them as we make progress.  Today we want to talk about the intercooler piping, specifically the cold side piping and the parts of the system. This is the piping that connects the outlet of the intercooler and the throttle body.  It is commonly referenced as the “cold side piping” because the charge (boosted) air has passed through the intercooler and is therefore cooler.

The OE cold side piping consists of three main components.  Starting on the right side of the image; we have the hard piping that connects to the intercooler and a soft rubber hose.  Next is the soft rubber hose itself, which we will talk more about later. Lastly is the throttle body connection, which is the oddest part of this system.  You can see why in the next image.

The above-mentioned intercooler hard pipe and the rubber hose are pretty common parts on modern turbocharged vehicles, but the throttle body connection is unusual from our experience.  The throttle body connection appears to be designed for a quick connection (and not so quick disconnection) during the vehicle assembly process. Unfortunately, this leaves a very odd connection flange on the throttle body itself.  Lastly are the fins inside the connection part; other than straightening the airflow entering the throttle body we don’t see many purposes these. We will be testing the effects and need for these in the near future.

Now let’s get to what we really wanted to talk about; BIG Silicone Performance Parts.

Mazda designed the Turbocharged 2.5L SkyActiv-G to function at a specified boost pressure and no more.  However, we fully intend to change this set boost pressure for increased smiles per gallon. With increased boost pressure comes more force and strain on the OE rubber hose.  Eventually, the OE rubber hose becomes too flimsy for the increased boost pressure and may expand or fail completely via a rupture.

So how do we develop a performance part to replace a rubber hose?  Well, there is one obvious improvement and another not-so-obvious change that can be made.  First, we use silicone as the prominent material for its excellent heat resistance and durability.  Next, the silicone is reinforced with five layers of fabric braiding to withstand the increased boost pressures.  Compare this to the OE single layer of reinforcement and you can see why this would make a big difference.

Now for the less obvious performance improvement; the CorkSport 3D Printed prototype is larger in diameter than the OE rubber hose.  Leaning on our experience with past intercooler piping development, we have found that increasing the charge air volume directly in front of the throttle body increases throttle response and helps spool the turbo faster, reducing turbo lag.  

Currently, we are still in the development phase but will be testing soon.  Stay tuned for future updates on the CorkSport Performance Boost Tube and other exciting products for your 2018 Mazda 6.  

-Barett @ CS

Stopping power for the Mazdaspeed6

With our goals to make more power, we often forget about the opposite requirement so speed…stopping. The CorkSport Big Brake Caliper Kit is a great place to start, however, if you wish you could stop even faster say hello to the CorkSport 13inch Big Brake Kit. Designed for serious stopping power, it includes 13” directional rotors, powder-coated 4-piston calipers, upgraded pads, and everything you need to install it on your Mazdaspeed 6.

Read on for a breakdown of all the components:

2-Piece Rotors

Lots of thought has put into the design of the performance rotors found in the CorkSport 13inch BBK. The upgrade to 13inch diameter rotors provides greater braking torque for an equivalent braking force (like how a longer wrench makes it easier to loosen a tight bolt). The increased diameter combined with a thicker 28mm (vs 25mm for OE) rotor ring provides better cooling as there is a larger mass to reject heat into.

In addition, slots were added to the friction surface to help sweep away any debris, brake dust, or gases that can otherwise affect your braking characteristics. Drilled rotors were not used as holes decrease your total friction area and increase the chance that the rotor will crack. Utilizing a two-piece design, we were able to decrease the overall weight of the rotor via center section produced from billet aluminum; while also helping dissipate heat from the rest of the rotor better. Semi-Floating mounting between the inner and outer sections allows for quieter rotor vs having a full-floating center section.

Lastly, the rotors feature directional internal vanes that promote more efficient airflow through the rotor which further increases the rotors ability to dissipate heat. By using curved vanes instead of the typical straight vanes, the rotor becomes directional and has to be used on a specific side of the vehicle; however, it also provides more efficient cooling. When the rotor turns, the curved vanes draw air through the center of the rotor and out through the edge, providing greater airflow than a straight vane and thus better cooling. There is another bonus to heat dissipation as the curved vanes have a larger surface area that will come in contact with air than an equivalent number of straight vanes.

Forged Calipers

Four-piston performance calipers manufactured from forged aluminum are included with the kit in a choice of powder-coated blue, red, or black.

Although each piston is individually smaller in diameter than the single OE caliper piston, the total surface area is increased so the braking force at a specific brake pressure is increased. Larger piston surface area means larger brake pads can be used as well. You also get more even braking force on each side of the rotor due to the opposed piston design. This encourages even pad wear, even rotor wear, and consistent braking characteristics. The piston diameter and material were chosen for optimum braking endurance and reliability. They are staggered in size, with the pistons on the leading edge being slightly smaller than the trailing edge pistons. This is another protection for even pad wear. Each piston is made completely out of stainless steel for its low conductive heat transfer. What this means is that the pistons themselves will transfer less heat to the brake fluid than an aluminum or steel piston, decreasing the chances of overheated brake fluid.

Performance Pads

Street performance brake pads are included with the kit. The street sports pads bridge the gap between street and trackpads. They are a more aggressive compound than the pads included with the CorkSport Big Brake Caliper Kit but are not a full track pad. They will produce less dust and noise than a track pad but still need to be warmed up for optimum performance. Should you need new pads or want to change to a different pad, you have a bunch of options from G-Lock, Carbotech, EBC, Hawk, and various other manufacturers.

Lines, Brackets, and Hardware

The remainder of the CorkSport 13inch BBK is composed of exactly what you need to properly and safely install the kit on your MS6. Coated stainless steel brake lines are included to remove any risk of a soft brake pedal and ensure the calipers are operating optimally. High strength billet steel brackets properly position the four-piston calipers on the new rotors using the OE bracket locations. All components are locked down using Grade 12.9 hardware with a corrosion resistant coating for lasting durability.

The CorkSport Mazdaspeed 6 and Mazda6 13” Big Brake Kit has everything you need to keep you safe at increased horsepower levels. If you’re looking for more than the stock brakes have to offer, let the CorkSport BBK be a part of your build.

Why Lowering Springs?

Everything to know about lowering your Mazda with lowering springs.

Whether you want the better handling that comes with the lowered center of gravity, or you want to rid yourself of the wheel gap eyesore.  Lowering springs will give you want you’re looking for.

For running the track, or a spirited drive through the countryside, CorkSport lowering springs are the upgrade you’ve been looking for. By adding lowering springs and lowering the center of gravity of your Mazda allows the car to stay more planted to the road.

One of the biggest things to note on stock suspension is how far upward the suspension travels when hitting a bump. It can make the car feel like it wants to lift off of the road; depending on how fast you’re taking corners. Lowering springs help to correct the car’s suspension travel when you hit a bump in a turn.

Corksport Mazda 3 racer

Lowering springs also have about 25% increased stiffness. For the Mazdaspeed platform, increased stiffness in the rear is a must. Mazdaspeeds like to squat pretty hard when hitting full boost, so any way you can manage to stiffen up the rear is a great modification for your car.

Adding lowering springs also gives your baby amazing eye appeal and a much more aggressive look. Whether you drive a Mazdaspeed3Mazdaspeed6Mazda 3, Mazda 6, CX-5, CX-3 or MX-5, lowering springs will get rid of that ugly wheel well gap. The result is a Mazda that carries a much cleaner and more aggressive look and gives you the ability to take it to the track if you want to.

Drop your Mazda for an aggressive look and better handling with the CorkSport lowering springs.

Some people want to drop their Mazda as much as possible, and some don’t. CorkSport lowering springs don’t deliver a super aggressive drop. If you’re not interested in scraping your front bumper on every road bump, the CorkSport lowering springs have the right drop for you, and provide the increased handling capabilities you’re looking for.

 

If you’re curious about other suspension pieces for your Mazdaspeed, check out our Struts and Shocks combo kits, that give you just what you need for suspension.