diesel | CorkSport Mazda Performance Blog

September 6, 2018December 26, 2023

Mazda’s Dynamic Pressure Turbo – An Introduction

The SkyActiv 2.5T has been around for a few years in the CX-9 however, things started to get interesting when the engine was dropped in the Mazda 6 for 2018+ models. While lacking a manual and not a true Mazdaspeed, it’s a step in the right direction for the enthusiast. With one of the new Mazda 6s in the CorkSport garage, we’ve been getting curious about where all of that 310lb-ft comes from. Well, we decided to call up Mazda and purchase a turbo to see how it all works.

There’s a lot to take in on the turbocharger and there are quite a few things that have changed from the K04 that made its home in the Speeds.

For starters, this turbocharger is pretty big. The wheels themselves are not large, with the compressor wheel very close in size to the old Mazdaspeed K04 & the turbine wheel only slightly larger than the K04. However, with the dual inlet turbine housing, 90° compressor outlet, and lots of attached electronics, the whole package takes up a lot of room in your engine bay.

The turbine housing is not far from the old K04. A large five-bolt inlet flange has two rectangular inlets to work with the dynamic pressure system (more on that later) and even a port where the EGR system sources its exhaust gases. The outlet is much simpler, using a five-bolt flange to mount to the downpipe, yet does house a surprisingly large wastegate port.

From a performance standpoint, the large wastegate should help eliminate boost creep but the turbine housing will likely need a larger scroll to get some more serious power out of the engine.

The compressor side is packed full of features. As usual, the wastegate actuator bolts to the compressor housing, however, Mazda has switched to an electric actuator. Interestingly, the bypass valve is also electric and is even mounted to the face of the compressor housing.

Some fancy casting design leaves a pathway between the high and low-pressure sides of the compressor and let the BPV decide when the passage is open or closed. These two electric actuators will mean easy and consistent boost control. The final plastic component on the housing we believe is a boost-assisted vacuum source for the vehicle. Finally, the inlet is a typical clamp connection while the outlet uses a 90° turn and two-bolt flange for better accessibility around the wastegate actuator.

With the housings removed, the CHRA of the dynamic pressure turbo is very simple & standard. Oil feed in the top, two-bolt oil drain in the bottom, and standard crossflow engine coolant ports. The compressor wheel is a cast 6×6 unit and the turbine wheel is a basic 11-blade unit.

We are looking forward to waking up the Sky-T in the coming months and making the 2018+ MZ6 into something a little closer to a Speed. Stay tuned, there’s much more fun to be had from the 2.5T!

-Daniel

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May 31, 2018April 17, 2023

3 Turbos and a Supercharger for Mazda

A year ago we were all complaining at Mazda saying “where is the forced induction?” and it looks like Mazda was listening.

First up is the Mazda 6 turbo which Mazda has priced to sell as you can get into a GT Mazda 6 turbo pretty affordably. Granted there is no manual gearbox but I can say first hand they are fun to drive and the torque from the boost is really addictive. I find it hard not to want to screw with people in the 6 since it has no visible exterior queues that it has a turbo. I will say we have already been tweaking on the car and found that it does respond well to modifications.

Second up is the SkyactivX which Mazda says will be available later this year. This engine is supercharged to allow it to be an HCCI engine, aka compression gas motor. The forced induction setup is pretty tricky and the initial look I have done with it I get we can crank it up a bit more to improve the efficiency of the intercooler to give it more heat capacity to allow you to use the boost longer in the car for high-performance driving. Until it shows up we won’t know for sure but we are looking forward to trying it out.

Third is the Mazda 6 diesel which uses 2 turbos. Mazda tried to release the 6 in the past but when they couldn’t match what VW was doing they declined to just “Send It” as the car didn’t perform as they needed it to and still hit the emissions targets without urea injection. Later we all found out VW was a cheating bastard which kept us from having the Skyactiv diesel engine here to crank up the boost on. About every publication in the planet has posted up about the 2018 Mazda 6 diesel being seen in the EPA parking lot for testing along with a pile of other diesel models. This is a good sign if Mazda says it will pass the US emissions and handed one over to the EPA we can expect a Mazda 6 turbo soon.

I am going out on a limb here and saying that besides the announced Mazda 3 Skyactiv we are going to get something fun in the new Mazda 3 ~ a year after the initial release. If you are reading this Mazda, please give us a Mazda 3 GT with a turbo motor.

-Derrick

August 12, 2016September 13, 2018

Could It Be True A New Diesel Mazda Is on the Way?

It has been a while since I touched on the subject of Mazda giving diesel a shot again in the United States. Back in 2012, it looked promising that we would be getting the Skyactiv diesel-powered vehicles like the rest of the planet. After working on the calibrations to meet the U.S. emission standards, Mazda discovered they could meet the emissions, but could not hit the power levels to give owners the driving experience Mazda is known for. Mazda wanted to hit the targets without the addition of urea injection to clean up emissions. They were squarely behind the diesels, even racing the Mazda 6 diesel in IMSA, 25 hours of Thunder Hill, and in prototypes. In the end, the diesels were abandoned, but the message was still there: Diesel models will be sold in North America, it just became a when.

Continue reading “Could It Be True A New Diesel Mazda Is on the Way?”

December 27, 2013

Mazda Axela Sport and the 6 Wagon Turbodiesel (Next Mazdaspeed?)

2014 Axela Sport Concept (New Mazdaspeed?)

Mazda recently released some concepts with Mazdaspeed exteriors. Could these be the next Mazdaspeed 3’s? The new Axela Sport with Mazdaspeed Exterior certainly has a sporty look, but there is no official word on if this is just a design concept, or if it’s confirmation of the next Mazdaspeed 3.

The hatchback will feature a strengthened chassis, some Brembo stopping power and a set of black alloy wheels. The end result is a stunning example of another great design from Mazda, a company that truly understands blending high performance and sporty style.

Whether this is the new Mazdaspeed or not, we look forward to more ideas and designs from Mazda, such as the Mazda 6 Wagon concept below!

Mazda 6 Wagon Mazda Design Concept

Also joining the 6 sedan lineup is a stylish wagon variation. Featuring subtle aero changes, new wheels and a leather wrapped dash. It will house a Mazda’s SKYACTIV-D 2.2-liter turbo-diesel engine power-plant. Rumor has it that we should be seeing this engine in the USA, so we have our fingers crossed. Turbo + Diesel + Wagon = the best of all worlds, at least we think so!

Stay up-to-date on the latest news and product updates from CorkSport.

2014 Axela Sport Concept (New Mazdaspeed?)

Mazda 6 Wagon Mazda Design Concept