2018+ Mazda 6 2.5T OEM Intercooler & Piping Analysis

We’ve already mentioned briefly that we have an upgraded intercooler kit in the works for the SkyActiv 2.5T, but now it’s officially time to dive in and get into how and why an upgraded intercooler kit is a good fit for your 6. To understand how to make a performance part, we first have to understand what makes the stock parts tick and where we can improve them, which is what we will be covering today!

For those of you that are new to the boosted lifestyle, I feel that I should go over a few terms that will be thrown around frequently later in this blog.

  • Hot Side Piping: Also known as just “hot side” or “hot pipes” this piping section carries the pressurized air (boost!) from the turbocharger to the intercooler. As it is before the intercooler, the air has not been cooled and the “hot” name is quite accurate (think 200-250°F. or even more on a turbo that’s too small). Shown above on the right side.

  • Intercooler: A basic heat exchanger. Air flows through the inside and is cooled by air flowing through the outside while you drive down the road. The same way a radiator works except with air inside instead of coolant. It is made up of three parts the “end tanks” and the “core”. The end tanks are what transfer the air from the piping to the core while the core is the actual heat exchanging portion. Shown front and center in the above image.

  • Cold Side Piping: Also known as just “cold side” or “cold pipes” this piping section carries the pressurized air from the intercooler to the engine. As it is after the intercooler, the air has been cooled to make more power. Shown above on the left side.

 

Now into the details…

The hot side piping must make its way all the way from the rear of the engine to the front of the car. The OEM piping takes a pretty direct route, and is a decent diameter for stock piping, starting & finishing at just under 2” inner diameter. This, however, is where the good things end.

To start, the two rubber sections of the hot side are single ply. These allow for good flexibility on install and to allow for engine movement but will start to expand on higher than stock boost levels, increasing boost lag and decreasing throttle response. In the image above, the main rubber section squishes under the small weight of the upper plastic section of the hot pipe. This isn’t even the main issue with the hot side piping!

The upper plastic section of the hot side has quite a few small radius bends, and a few areas where the pipe reduces in diameter severely, affecting the maximum flow and restricting the power of your 2.5T. Check out the worst area below, it’s tiny!

And what might be causing this reduction in diameter you may ask?

That’s right, its clearance for a hose clamp. Mazda, I’ve got to call you out on this one, couldn’t you have just rotated the clamp, and kept the diameter in the pipe? Anyways, on to the intercooler itself.

The intercooler itself isn’t too bad, a decent sized core with lots of fins to help cool as good as it can. That being said, there’s still plenty of room for improvements. First: make it bigger. The intercooler mounting could’ve been simplified to get more width, and there’s a bunch of room to go thicker. While thick is not the best for heat transfer efficiency, it will still help cool off the air better. Height is already more or less maxed out without cutting up the crash beam, but we should be able to make enough extra volume elsewhere to make a big difference.

Intercoolers are a delicate balancing act between cooling efficiency and pressure drop. Cores that cool extremely well usually have a larger pressure drop (loss of pressure from inlet to outlet) and vice versa. With the high fin density of the OEM intercooler, we can expect a relatively high-pressure drop (2-4psi would be my rough guess) but pretty good cooling. From early dyno testing on the CorkSport Short Ram Intake, the intercooler does a good job cooling but loses power on back to back dyno runs. I expect that this is the intercooler “heat soaking”. Heatsoak is what happens when an intercooler is undersized or is not getting enough airflow, it heats up and is no longer able to cool the boost off, robbing you of power.

The two images above show the real Achilles heel of the OEM intercooler and what is likely causing the heatsoak issues: the end tank design. Since the charge air enters and exits the core at an upward angle, it’s being directed away from the lower runners of the core. There is a sharp angle that would be hard for the air to turn, meaning the bottom three internal runners (shown with the red box) are likely not actually doing much. So you’ve got intercooler taking up space that is likely not doing much… We aim to fix this.

The cold side of the system is actually pretty good-inner diameter of just under 2.25” on the ends (even larger in the middle) and a short path into the throttle body. We’ve already covered the basics of it when discussing the upcoming CorkSport boost tube HERE. Like with the hot side, the rubber connector is prone to expansion under increased boost levels. While the CorkSport silicone boost tube will still be coming on its own, we plan to offer something even stiffer that is optimized for our upgraded FMIC kit.

Much more information to come in following blogs as we’ve been busy working away on this project. Stay tuned for full details on the upcoming CorkSport FMIC kit, and if you’ve got any questions, leave them down below.

-Daniel @ CorkSport

3rd Time’s the Charm

We all know the saying the 3rd time is the charm and this year’s SCCA National Championship Runoffs was no exception to the rule.  The past 2 runoffs I have not made it to the finish.  In 2016 at Mid-O I was hit on the first lap and punctured my left front tire.  At Indy, I retired as we developed a fault in the ECU from some beta software we were running and the car dropped into limp mode and I wasn’t able to maintain full throttle.  

We have been working on the brakes for the past 3 years and during the season it limited us from running the car as much as we like.  We have also been chasing a fault/error with the ECU/control system of the car. We were still able to get the car enough starts and race finishes to get qualified for the runoffs in Sonoma.   Granted the car was not happy at most of those races and it was a struggle to get the finish.

2 weeks before the runoffs we sorted out the ECU problem and were confident enough in the car to race it.  The backup plan was to race my Spec Miata if we couldn’t get the Mazda 3 fixed as I ran it this past season as well and had enough starts/races.

With the Runoffs at Sonoma it was within 1-day driving distance unlike the past 3 runoffs at Daytona, Mid Ohio, and Indy so I got to try out the new (to me) truck and trailer.

I had raced at Sonoma one time prior, so the track wasn’t totally unknown like Mid-O and Indy, which all I had was simulator time so I was able to get up to speed quickly on a test day and find out what I needed to work on for chassis setup and driving.  The driving was easy to adjust, look at the data, see where the driver was sucking and had to man up to keep a foot to the floor in some sketchy corners.

The car, on the other hand, had what we call “a good problem to have”, too much power.  We have been running a torsen style differential in the car which works pretty good in a straight line and relatively flat tracks.  Sonoma is not a flat track which unloads the car 3-4 times per lap. With the Mazda 3 and the amount of torque it makes means I was unloading the tire enough for it to spin the inside tire.  Most people think what is the big deal with a little tire wheel spin? It is a problem when you enter turn 10 at Sonoma at 97MPH and you start lighting off your right front tire. Look at the picture below and you can see that front inside tires is barely on the ground and the rear isn’t.  The speedometer would jump around and you could see the right front wheel speed turning at 5-10 mph more in the data.

We tried several suspension changes and driving style changes to make the best of it but in the end, we were way off the pace by 2-3 seconds of the rear wheel drive cars in the class.

The good part about not being at the front of the field, there was zero stress when race day came.

Like any race there was a fun challenge, we would be heading into turn 2 blind as the race was at 4 pm in the afternoon and the sun would be shining directly down the hill.  Since I wanted to see the end of the race I a little cautious at the start and Ali in the other Mazda 3 got around me at the start.

We fought it out for 8 laps and he went into turn 6 too hot and I was able to get under him and pass him on the inside.

After a few laps I put a 4-5 second lead on Ali I was basically in no man’s land, slower than the front guys and faster than the back half of the field so I spent my time working on tire management (it is easy to overheat your left front tire at Sonoma) and made it to the end of the race.

My official finishing place was 10th but after some adventures in tech, I was moved to 9th in the final results.  This isn’t where I wanted to be by any means but the 3rd time was the charm and I made it to the end of the race.

Huge thanks to the support we get racing the car from CorkSport, BFGRacing, Monarch Inspections, G-Loc Brakes, and Mazda Motorsports.

 

Derrick Ambrose

Exhaust Scavenging

In this blog, we are going to SHOW a demonstration of exhaust gas scavenging.  Instead of a lengthy blog full of text, we’ve opted to create a video that demonstrates the effects of exhaust gas scavenging for both good and bad designs.  

We will be comparing the prototype CorkSport performance exhaust manifold, developed for the Mazdaspeed 3 and 6, to the OE exhaust manifold.  

Exhaust gas scavenging within a manifold is the process of one cylinder runner, pulling (aka scavenging), the exhaust gas from an adjacent cylinder in a continual cycle.  Now enough talk, to see an awesome example and an awful example of exhaust gas scavenging check out the video below. BONUS! Not only do you get to see what optimal scavenging looks like, but this is also the first sneak peek of the CorkSport Performance Exhaust Manifold…

Video Link: https://youtu.be/RtydboDbwpQ

We hope you found this as interesting as we did!  Stay tuned as we continue developing the CorkSport Performance Exhaust Manifold for the Mazdaspeed platform.

 

-Barett @ CS

Mazda 6 Turbo and CX-9 Short Ram Intake

That’s right, it’s time to start making more power on the SkyActiv 2.5T. We are proud to introduce the CorkSport Power Series Short Ram Intake for 2018+ Mazda 6 equipped with the 2.5 Turbo Engine and 2016+ Mazda CX-9 . We replaced the restrictive factory airbox with a free-flowing intake system that was designed to help your turbo breathe significantly better. The SRI offers better performance, sound, and looks in an easy to install package. Read on for full details, and be sure not to miss the sound clips in the video below!

This CorkSport Short Ram Intake was designed specifically to get the best the 2018+ Mazda 6 2.5T and 2016+ Mazda CX9 has to offer. From the precision machined MAF housing to the high flowing filter, each component in the CS system offers an improvement over the stock counterpart while retaining great fit and finish. All mounting hardware, brackets, and clamps are included to make your install quick and painless.

Starting at the OEM turbo inlet pipe, the factory airbox utilizes a ribbed and flexible rubber elbow. While working well enough, the ribs induce significant turbulence into the intake tract. The CorkSport intake replaces this elbow with a smooth flowing silicone elbow. In addition, the silicone is 4-ply reinforced with nylon to eliminate any chance for volume reduction under wide open throttle.

Next comes the MAF sensor housing. The MAF sensor essentially reads the volume air that is entering the engine so the ECU can adjust tuning to suit. Since the OEM unit does a good job here, it was imperative that the CS MAF housing matches to ensure no check engine lights or tuning issues. The CorkSport MAF housing is precision machined from 6061-T6 billet aluminum to match the OEM housing to ensure no CELs, no tuning issues, and great flow.

Finally, the CS SRI uses a performance AEM dry-flow filter. A high-quality filter like this is long-lasting, reliable, and can be washed and reused. It has superior filtration to the OEM filter, while also allowing more airflow into the intake tract.

Now for what you’re all really interested in: power gains. By removing the restrictive OEM airbox and turbulent intake elbow, we were able to pick up 8-12WHP from ~4000RPM out to redline. This power bump comes with no tuning changes and with identical testing conditions. Check out the dyno graph below to see for yourself! Note: the variance in low RPM (2800 and lower) is due to difficulties associated with dyno testing an automatic vehicle.

Freeing up a few extra ponies is great but what you will really notice is the added engine and turbocharger noise. That restrictive airbox does a little bit too good of a job at dampening out all the fun sounds that come with a turbo. We were honestly a little surprised by the flutters, whooshes, and psshh noises that come with the CorkSport SRI. You also gain a little extra engine induction noise under hard acceleration. The extra noise is enough to be fun when you want it but not annoying or distracting when you don’t. Watch the video below to see what it sounds like.

As with most CorkSport products, this SRI kit comes with all the clamps, hardware, and even a support bracket for the MAF housing to ensure you have an easy and quick install.

The CorkSport SRI for 2018+ MZ6 2.5T & 2016+ CX-9is a great modification whether it’s your first or the just the latest on a long list of builds. It provides a noticeable power gain, adds some extra fun to your ride, and will support future mods down the road. Pick up yours today!

Be sure to contact us with any questions you may have, we will be happy to help!

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.