Mazdaspeed Cast Exhaust Manifold

Today is a huge day for the Speed community; one that has been coming for a long time with both celebration and frustration. Never the less time is up and this project is ready for the community as a whole!

We are proud to announce the Performance Exhaust Manifold for the Mazdaspeed 3 & 6! With over 2 years in development, the MPS exhaust manifold has been long waiting, but for good reason. A project of this scale does not happen overnight; many variables have to be considered, evaluated, and verified.  

I’m confident you have seen “leaked” images from our 6 Alpha and Beta testers over the recent month, but we can make it official.  

CorkSport

But with so many options currently available what makes the CorkSport option compelling? Why should you care?  

That’s a great question and one that can easily be answered with multiple great reasons. The most obvious is the design: this includes the overall shape and the type of material & manufacturing.  

Mazdaspeed Exhaust Manifold

Material & Manufacturing: In our initial investigation and vetting of this project we strongly considered two primary manufacturing methods; Casting and Tubular fabrication (check out the blog here). In a nutshell, we opted for a cast manufacturing method because it reduced the chance of failure modes, reduced the overall size and weight, and gave us more flexibility in design.  

Like most exhaust manifolds, we opted to use 304 stainless steel because it is corrosion-resistant, handles heat well, and is a common and cost-effective material.  

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Following up is Design: The list of details that went into the design is far too long to list here, but we can cover the major items that define the CS Exhaust Mani. With investment casting, we had a lot more flexibility in design with the bend radius, diameters, and wall thickness of the individual runners. This allowed us to increase the inner diameter of the runners to 1.59 inches, achieve a 0.200-inch wall thickness, and fine-tune the path and bends of each runner to optimize runner length and flow.  

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With that flexibility in design, we were able to increase peak flow and improve flow balance per runner. Overall we were able to increase peak flow 45% over the OEM manifold and 33% over the XS Power V3.  

Next up in design, and arguably the most exciting and unique aspect, is the modular flange system.  

Mazdaspeed Exhaust Manifold

This is unlike any other manifold available for the Mazdaspeed today…you can choose your flange between OEM Stock Flange, Precision V-Band, or T3. Sure all these options are available today from other options, but none are modular. Say you pull the trigger on the OE Stock Flange today, but a year from now you want to upgrade your build to a Precision V-band flange. With any other manifold, you would have to buy another $900+ manifold to get the new flange, but with the CorkSport Exhaust Manifold, you just have to get the new flange elbow for your setup. This is MUCH MUCH cheaper and easier to change!

CorkSport

Speaking of install, compared to the typical performance exhaust manifold the CS design is cake to install. With the modular design, you are not fighting the entire bulk for the manifold and flange at the same time. You can leave you turbocharger unmoved connected to the downpipe and intake system, you just install the flange elbow after the manifold is in and bolted to the engine.  

Mazdaspeed Exhaust Manifold

Making life even easier…we opted to develop a pre-fabbed dump tube (screamer pipe) for the Tial 44mm EWG. This is an optional feature for the kit, but one we highly suggest because it’s just so damned easy. Designed for MPS 3 and MPS 6, it fits around most standard downpipes and dumps below the sub-frame right behind the drive axle. Also included with each kit is a SS heat shield that is required for the GEN1 and GEN2 Mazdaspeed 3. You Mazdaspeed 6 guys just get a cool garage ornament.  

So how does the CS exhaust manifold stack up on power? 

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First up is a fully bolted CST4 MS3 with a 6th port fuel system: Comparing the CS EM to the OEM EM, this drop-in test we found that the turbo was spooling faster, carried more mid and upper range power and held that gain through to redline. Overall it improved power under that curve which is what truly makes a car fast and fun to drive.  

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Next up is a fully bolted and built CST6 MS3 with 8th port fuel system: Just like the previous graph, we saw an improvement in spool, mid and upper rpm ranges, and carried it to redline. The difference here is the exhaust manifold we are comparing. This is showing the difference between the CS EM and the XS Power V3.  

With that being said, the CorkSport Exhaust Mani has been proven to 685whp on this same car and with the CST6. We are confident the CS exhaust manifold has far more capacity to support; if we have anything to do with that we will prove it. 

Mazdaspeed Exhaust Manifold

Lastly is sound…we’ve been asked a lot about the sound. How will it affect the sound? Will it sound like a Honda now? Will it be louder?  

We knew the sound was critical because let’s be honest…we are all car guys/gals and Mazdaspeed has a great unique sound to it. We did not want to lose that so we did our best to hit performance goals without sacrificing the Mazdaspeed grumble.  

One of our Beta testers put together a great video comparing the sound of OEM vs CorkSport. The car is a GEN1 MS3 with a built engine, full bolt-ons, CST4, and Cobb Exhaust system. Check out this video link for sound!

In our design, we kept a varied length runner design to help maintain the Mazdaspeed grumble. We believe we succeeded in keeping that classic grumble, but also refined the sound a bit. We like to describe it as exotic. Either way, the grumble lives on, and honestly, none of our beta testers can stop grinning ear to ear with every WOT pull.  

With that being said act fast! We know these are going to fly off the shelf and we are going to do our damn very best to keep them in stock for everyone, but don’t wait!

Grab yours here!

Thanks for tuning in with CorkSport Mazda Performance.  

-Barett @ CS

Barett’s 1/2 Mile Mazdaspeed 3 Build – Part 1

Hey Everyone, if you don’t know me already I’m the engineering manager at CorkSport Performance & @Halfmilespeed3.  I want to make a formal greeting and invite you to follow along as I take the next huge step with my personal build.  I drive a 2009 Mazdaspeed 3 that has been through many iterations.  I bought it nearly 6 years ago and have since used it in excess to support CorkSport R&D.  Hundreds if not thousands of passes on the dyno with so many parts…it’s been a beaten test mule.  The time has come to set a focus.

2007-2009 Mazdaspeed 3 Crashbar

Now, with the 4th engine going in it, I’m setting the build focus for ½ Mile Drag Racing.  Power, Aero, and some “Mad Scientist” R&D is going into this build.  (see WTF is THAT)

Mad Scientist Add-ons
600hp Mazdaspeed Build Path – CorkSport Barett’s 2009 Mazdaspeed

My goals are 700whp on the CST6 stock flange (with Will @ PD Tuning giving it the sauce) and 180mph in the standing ½ mile.  I plan to play in the 1320, but half mile is the focus.  My first event was going to be Never Lift @ Coalinga Munical Airport in Late March, but with recent events, this was canceled and a new date has not been set.  Fingers crossed the country gets through this and the next events hosted by Shift S3ctor Airstrip Attack in June and November hold.

Back to the build…I know that pushing a Mazdaspeed through the air at 180mph is a lofty goal and that physics are against me.  With the help and advice of Aaron O’neal @ English Racing I am exploring high-speed aero design. 

Gen 1 Mazdaspeed Parts

The primary goal is stability at high speed.  I want to be safe in this type of racing so I need to do what I can to make the car stable and predictable at speed.  This means I need the car to cut through the air as smoothly as possible, and if possible, generate downforce. 

To do this I’ve made a prototype drag wing (which I will share more detail on in a later blog) per the advice of Aaron and my research.  This wing is two feet long at the top! And with the closed sides, this should reduce the amount of lift generated at the back of the car.

There is still a lot more work to do here but you get the idea so far.

Splitter Mount
CorkSport

Upfront I am still very much in the conceptual phase of design.  Nearly the whole front bumper will be sealed off with a single sheet of ABS plastic formed to the front of the car.  The only opening will be a rectangle about the size of the intercooler for cooling airflow.  I also plan to build a chassis mounted splitter.  The red parts in the image above are the one-off brackets I designed to mount the splitter to the chassis and still be able to adjust the height (Again I’ll share more detail in future blogs as the prototype comes together).

CorkSport

The other less intuitive aero bit I’m doing on the front of the Speed is hood venting.  Thanks to Jonathan Castro @ JC Speedworks for the hood vent I’m able to kill two birds with one stone here.  If you’ve done any type of racing you know heat is a killer and must be managed.  With this hood vent, I am both evacuating any high-pressure air build up in the engine bay and promoting more efficient airflow through the intercooler and radiator. 

With the 300 miles I’ve put on the car, I can already see a huge difference in normal operating temps.  Maybe more vents are in the works? 😉 Oh and shout out to @mz_rawr (Aaron Maves) for cutting holes in my hood.

CorkSport Mazdaspeed 3 Transmission Mount Blog

In the process of getting the engine and transmission together, I wanted to fix a 2nd gear drop out issue I had.  Over a weekend @thatonepnwguy (Bryce Peterson) and I split my transmission and replaced the shift forks.  We certainly did it the wrong way and had to chase some balls around and get them back into their respective locations; despite all that, don’t be afraid to tear into things and learn the hard way. 

How To Achieve 400 WHP In Your Mazdaspeed Blog

The powerplant made it in the car and is running great.  Right now I’ve got about 300 miles on the engine.  I’ve been working out some little details with heat management and setup of the Vacuum Pump (WTF is THAT).  I am just now starting to do logs and tuning with Will Dawson at Purple Drank Tuning.  With these goals, I still intend to keep the car street legal and driven on a nearly daily basis (I wish you could see the stares I get from people).  I’m putting this out to all of you as an invite to follow along with the build on Instagram @halfmilespeed3.  All the inside info and goodies are there for you to see along with @corksport for other stories and build updates.  I’m stoked for this season and to explore a racing series that has largely been untouched by the Mazdaspeed community.  I will be finding limits and new challenges for the platform that I hope to overcome.

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 to not 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 it and 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