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
We talk a lot about dyno testing and seeing improvements with CorkSport goodies but we rarely talk about what dynos are and why dyno testing should be a part of your build. While e-tuning using logs and v-dyno works great, tuning on a chassis dyno can be quicker and is a just a bit safer; since let’s be honest, 4th gear WOT pulls in your local area of “Mexico” can get a little sketchy sometimes. Keep reading on for some advantages of knowing your dyno numbers.
To start off, I wanted to share a little bit of knowledge of what a dynamometer (dyno for short) is and how they work. Dyno is a broad term for a machine that measures force, torque, or power. In the automotive world, we typically think of a chassis dyno that measures torque through the drivetrain of a vehicle, however, for high-level suspension tuning, shock dynos also exist. Now some of you may be surprised to hear that dynos measure torque, not horsepower. Torque is much easier to measure and can be easily converted to horsepower (HP equals torque times RPM divided by 5252 for those curious).
There are a couple names of dyno you have likely seen get thrown around: Dynojet, Mustang, Dynapack, and DynoTech to name some of the most common. Each measure power a little differently but for the sake of keeping things concise, each uses a known or controlled “resistance” to fight the vehicle’s torque that is being produced.
Dynojet and some Mustang dynos use a physically heavy drum while Dynapack, DynoTech, and other Mustang dynos use electricity or hydraulics to control the dyno’s “resistance”. Each type of dyno has its own set of advantages & disadvantages but the most important thing to remember is that they will read differently for the same vehicle. This means if you are getting your car tested or tuned on a dyno multiple times, be sure to use the same type, and better yet same exact dyno, to really see how your build has affected your horsepower & torque.
On to advantages of getting your car dyno tested. While most are not “make it or break it” changes, dyno testing can really take your build to the next level.
Bragging Rights: While an obvious one, dyno results make it much easier to compare your car to another since you have hard data to back you up. This is especially true if you are using the same type of dyno. On a lighter note, comparing your car to someone with a well-documented build can help you decide what your next mod will be.
Ease of Tuning: Consistent and accurate pulls can be had back to back on a dyno, without having to drive out to your “dyno road” after every small tuning change. In a properly setup environment, pulls will show only tuning changes instead of having to worry about every little variable that comes with on-road pulls. If your tuner is in town, having them live tune with your car right in front of them can turn a multi-week e-tuning process into a long afternoon. Plus, you won’t have to worry about an expensive ticket from the local boys in blue.
Monitoring Car Health: Friend has the same car, same mods yet are making much more horsepower? Dyno testing can show things like this that may indicate a big problem with your ride. Removing the “driver mod” from racing your friend light to light can help determine if there’s something more going on. In addition, having hard data on power & torque numbers can tell you when to stop pushing for one more psi, keeping your ride on the road and not in pieces.
New Mod Validation: Bought a part and want to see what it’s doing for you? A dyno before and after is a great way to validate your new mods and see what your next step should be. In addition, you may find out there are more benefits to a part than just max power gains. Maybe that newest part only gave you +2WHP at peak but shows gains of 10-15 through the middle of the rev range, or you can hold power to a higher RPM. Analyzing dyno graphs for more than just peak numbers is a powerful tool that can indicate how a part changes how a car feels.
Obviously, not everyone has access to a dyno and it is usually expensive to use a dyno for more than a few pulls, however, it is worth it and can give you some much-needed info about your ride while keeping you & your ride safe and out of legal trouble.
Looking for a dyno for your car? We are hosting the 2018 CorkSport Dyno Day in August. Dyno runs, food, a car show, and even drag racing are all on the agenda. Check out the Facebook event page for full details & don’t be shy if you don’t have a Mazda-we had a Fiat 500 Abarth on the rollers last year!
Hope to see you there!
Yes, I said the “A” word, but before we dig into the detail let’s talk steering wheels in general.
The steering wheel in your Mazda (and most all other cars) is probably one of the most used yet disregarded parts of the vehicle. Its round, it has buttons for controls and the horn, and in modern cars and airbag which could save your life one day. More or less we don’t notice because it just works, but what if we could make that a much more exciting part of your Mazda?
There are few, if not any, other components that you interface with more than the steering wheel so why not give it the attention it needs without sacrifice? At CorkSport we did just that.
Every CorkSport Performance Steering Wheel is designed with you, The Driver, in mind. We want you to be connected to your car and the experience it can provide you every single day. The performance design is inspired by race only steering wheels without the sacrifice. Thick grips with countered thumb grooves provide a secure and comfortable control surface. High quality smooth and perforated leather is used for durability and breathability in tense driving situations. These all come together without compromise, retaining your OEM controls, horn, and most importantly the airbag.
Now back to that “A” word…
A few years ago we introduced the CorkSport Performance Steering Wheel for the 2nd Generation Mazdaspeed 3. We were super excited to bring such an awesome performance part to the community and even more stoked by how much love that steering wheel has received over the years. Today we are happy to announce that a select few of the CorkSport Performance Steering Wheels are getting some extra awesomeness real soon.
Say it with me…Alcantara…
That’s right; we’ve heard you and we’re calling you out. In a very short time, we will be launching the Alcantara Leather option for the 2010-2013 Mazdaspeed 3, 2016+ MX-5, and 2014-2016 Mazda 3.
If you’ve been on the edge about a CorkSport Performance Steering Wheel; well the wait is over. I can’t say enough what a change a steering wheel makes to the driving experience. It really is like getting a whole new car and now it can be even better with Alcantara.
Don’t wait or it might be too late!
Have you ever felt the love?!
Here at CorkSport, we are known for paying attention to the little things when it comes to our customers. Often, you’ll see we send out some extras like the following, to pass just a little bit of extra joy to our customers!
We do Little things, like notes, cards, drawings, and candies. Who doesn’t need a little extra fuel during the install?
We do Big things, like Christmas Packages for Deployed Soldiers, unexpected gifts for customers going through life changes, and surprise drop-offs when we’re in your town. Always looking for a way to give our thanks for your support!
We do Baby Things… to welcome the newest members of the CorkSport Family to the world, not to mention that little T-shirts are just plain awesome!
And Holiday Things, to spread joy, cheer, and love when the season is just right. Not just Christmas, we’ve been known to hit Valentine’s day too, (warning here that sometimes Girlfriends get jealous if they see the valentines we send out)
Sometimes there are silly things, like drawings, games, and toys. Of course, having a signed autograph from Derrick may be silly to some, but SOLID GOLD for others.
Really, we just love doing all the things. No matter what you get or see as an ‘extra WOW’ in your packages, just know we did it out of love and thanks.
That is Why we do it.
To bring that extra bit of joy to your day, as if receiving CorkSport parts wasn’t enough. It’s our favorite. Surpassing customer expectations and seeing their joy come right back to us via social media. As you can see our customers share the love right back when they post our simple little tokens of gratitude.
Have you been one of the lucky few to receive a bit of Corksport WOW in your life? We’d love to see you post it up with #CorkSport or tag us with @CorkSport.
Nothing satisfies the CorkSport Team more than seeing happy, satisfied customers!