Recipe to Make a 500 HP Mazdaspeed 3

400 Whp not enough for you and your Mazdaspeed3? 

Searching for more power for your speeds MZR engine? 

Are you building your DISI motor, and trying to figure out your next setup? Say no more… 

This next Mazdaspeed-focused blog is going to focus on making some big power numbers, and what it takes to get there. Now is the time to go beyond the scope of the 400-wheel horsepower to look at what it takes for 500 horsepower at the wheels. 

In our 400 WHP blog, this is not an all-inclusive guide and the only way to achieve these power levels… However, it’s something that’s been tried and tested for years and proven to be a reliable method of making the power you’re after. We are aiming to educate you in the best way to make the most out of your MZR engine.

Let’s get started 

With the MZR engine being out for over 10 years, it’s had a lot of time under the knife. We know how the engine responds to different airflow mods, tuning characteristics, fuel, etc.

We also know that 400 Whp is about the limit of the stock bottom end on the Mazdaspeed 3. If you have a Mazdaspeed 6, then you can assume it’d be a bit less given you have AWD and need to account for further drivetrain loss.

It is beyond this point that the motor is in danger and could potentially let go. Keep in mind that at 400 Whp you are nearly doubling OEM power output, and that’s a lot of strain on those pistons and rods that were never designed to endure that power long term.  If you are wanting to go beyond 400 Whp then you should know that you are also looking at the price tag of a Built motor.

What it takes to Make 500 Whp In Your Mazdaspeed
CorkSport

Now, if you are relatively new to this, and aren’t very familiar with the basic building blocks of the platform such as the Cobb Accessport, and Upgraded Fuel Pump Internals, then I invite you to read our 400 Whp Blog to build a good foundation. Do you feel you have a good understanding of what it takes to get to 400 Whp? Then you are ready to read on!

When you’re at a point in your build that you are seeking 500 Whp then it’s safe to say that you probably have gotten the more tedious stuff out of the way… You probably have about every bolt-on modification, and you understand what it’s like to work with a professional tuner.

That being said, let’s do a bit of a recap on the 400 Whp mods, so you have a good idea of where we need to go from here.

These are all the recommended/required mods to increase engine airflow and efficiency to make 400 WHP.

Basic Bolt Ons: (Less Expensive / easily removable parts )
Fuel Pump Internals
3.5” Intake (Requires ECU relocation or battery box)
Upgraded EBCS
Upgraded Map Sensor
Upgraded Downpipe
Upgraded Intercooler
Upgraded Catback Exhaust
Oil Catch Can

Advanced Bolt Ons: ( More expensive / more difficult to remove )
Upgraded Turbocharger
Upgraded Intake Manifold (Optional but Recommended)
Upgraded Exhaust Manifold (Optional but Recommended)

Fuel:

Stock Fueling on Pump Gas usually nets around 330-350 Whp depending on octane and gas quality.

Stock Fueling on E85 blend fuel usually nets around 370-390 Whp depending on Tune aggression and also Quality of the gas and E85.

With Aux fueling such as port fuel, or methanol you can easily bump up over the 400 Whp mark and beyond. (I’ll get into the differences more in a bit)

Putting down 500 Whp pretty much requires many of the same mods that 400 Whp does, BUT the primary game changers are the Advanced Bolt On’s and Fuel.

(If you’d like to refresh your memory on the basic bolt-ons and how they affect your Mazda please refer to the 400 Whp blog.)

I’m ready for more POWAHH

In the grand scheme of things, making the 400whp is relatively easy and affordable considering it can be done on the stock block. With bolt on parts, fuel, and a tune you can easily hit that number. But as soon as you want to make more, you’re looking at a built engine, as previously mentioned, And that’s a whole new can of worms.

So, what’s all involved in a built motor? That’s a bit of an open-ended question as there are so many variables to take into consideration. However, “built” engines usually contain forged pistons and rods with upgraded bearings to handle more abuse. From there, the complexity increases as you get into port work, cams, etc. I will touch on that a bit more later. 

Fortunately for you, most engine builders have their entry level engine ready to handle 500 wheel horsepower and it’s a pretty basic build that features stronger internals. But, the tedious stuff like port work is usually reserved for the higher tier engines that are usually built for more power.

I won’t get into the engine building side of things, as that could turn into a whole other tangent. But you can assume that a built motor may cost you anywhere from 5k and up dependent on the level of motor you go with. From there we can start piecing together our 500 Whp build.

What it takes to Make 500 Whp In Your Mazdaspeed
CorkSport

Let’s Talk TURBO’S (Crowd Cheers) 

The turbo is the heart and soul of the Zoom-Zoom, so it seems like a suitable place to start.

What it takes to Make 500 Whp In Your Mazdaspeed with the CSt5 Mazdaspeed Turbo
CST5 Turbo Upgrade – 2006-2013 DISI MZR

As we know, the CST4 is happy up to around 400+ Whp. Which is why it was the recommended turbo in the 400whp blog. But now we are ready to take a step up to the CST5 Turbo for the Mazdaspeed which is happy up to… You guessed it! 500+ WHP. With the ability to hit 20 PSI by 3500-3600 RPM and Carry out 30 PSI it really packs a punch for its size. You may be needing to upgrade your intake to pair to the T5, I’d recommend our Power Series 3.5” Intake I mentioned earlier. It will come with the 4” coupler required to mate up to the turbo.

The turbo is available with an internal gate, or an External Gate so you can choose what works best for you. Both options can hit the same power numbers.

Upgrade Your Turbo with the CST4

Let’s Talk Fuel

What it takes to Make 500 Whp In Your Mazdaspeed
HPFP System

“What options do I have for bigger injectors?”

At CorkSport I get this question rather often. Unfortunately, I must tell them “There aren’t any”

Without going too off topic here I will explain why.

Our cars feature a Direct Injection fuel system or DI… And by today’s standards, it’s a bit primitive. The MZR DISI was one of the first pioneers of modern DI, which is probably why the OEM high-pressure fuel pump can’t even sustain the full potential of the factory injectors. Don’t worry, the CorkSport Fuel Pump internals fixes that problem.

Port Injection is simple and easy to maintain. It works by spraying low pressure fuel into the intake runner where it atomizes in the air stream before entering the combustion chamber.  For car guys, it’s fantastic and easy to swap out injectors when you are ready for more fuel.

Direct Injection takes a whole new approach. Instead of the fuel going in through the intake manifold, it goes DIRECTLY into the combustion chamber.

In order to overcome the force of compression, the fuel must be highly pressurized in order to atomize correctly. It also must deliver more volume in a shorter amount of time. This is why your Mazdaspeed has a high-pressure fuel pump. 

This causes a whole lot of complications for injector developers because things like fuel pressure also become a huge variable when attempting to create a larger Direct Injector. The bigger the hole on the injector, the more fuel pressure is required to create adequate atomization. Combining that with the rarity, and size of the Mazdaspeed platform, it’s just not worth it for any manufacturer to develop one.

So, what’s the solution to getting more fuel? Well… As previously mentioned, you pretty much have 2 choices Port Injection or Methanol. Since both of these are considered Auxiliary fueling, they are controlled by separate controllers, unless you want to ball out and get a Motec ECU that can control the OEM engine systems, as well as your port fuel.

Choosing which system, you want to go with solely depends on your power goals, and how much money you have to spend. Those 2 factors are pretty much the only question you need to ask yourself.

What it takes to Make 500 Whp In Your Mazdaspeed
Leo dropping that cash on a port Injection fuel system

Methanol – Cheap and simple 

Port Injection – Expensive and Reliable 

You must remember that the OEM fuel system, even with E85 in your tank is only good up to around 370-390 WHP. So, everything beyond that is supported by your AUX fueling. If your extra fuel system stops spraying for any reason, that could lead to catastrophic damage depending on how much you’re relying on it. When you’re just trying to nudge over the 400 whp mark on a CST4 or CST5 then Methanol is usually fine in my opinion. But beyond that, I’d be concerned with the reliability aspect.

When you have a properly set up port fuel kit (Manifold with fuel rail required) it behaves almost as if there is no AUX fueling system. This is especially the case when you have it all integrated into your factory gas tank and don’t need to fill up a separate cell. A quality Port Fuel Kit is pretty full-proof.

You’ll have to make the decision that’s best for you, but I’d recommend a port fuel kit to support 500 Whp, vs a heavy spraying methanol kit.

Mazdaspeed Intake Manifold with CorkSport fuel rail
CorkSport Manifold With Fuel Rail For Port Injection

Let’s Talk Manifolds 

Manifolds are responsible for transferring all the air in and out of the motor from their respective cylinder. This job is an important one as it needs to distribute the gases as evenly as possible. The more even the flow, the better the performance!

On the Mazdaspeed Platform, the OEM intake manifold is known to be the bigger restriction over its exhaust counterpart. With very unequal flow distribution across the 4 runners, it has been proven not only to restrict power but also cause premature wear and tear on cylinder #3; here’s why.

This is caused by “over-feeding” air to #3 in comparison to the other cylinders. Over time this #3 is actively running leaner than its counterparts which is why it’s been deemed the most common cylinder to blow if an engine does give way.

CorkSport Intake Manifold for Mazdaspeed shown to provide example of even Flow
CorkSport Intake Manifold shown to provide example of even Flow

It is because of this, that I always recommend a CorkSport intake manifold for even stock power levels. It may not be required to make 500 Whp, since you can essentially just turn up the boost to counteract the restriction. But in the name of reliability and efficiency, you should always try to help your engine breathe with the most minimal effort while also helping it maintain its health. 

Mazdaspeed engine making 500 WHP
CS manifolds, FMIC, and 3.5” intake in picture

The OEM Exhaust manifold may not be as bad as the intake manifold, but it’s still not ideal, especially at this power level. A performance exhaust manifold needs to be designed with exhaust scavenging in mind. 

Exhaust scavenging is a very cool effect. The exhaust gases leaving the combustion chamber travel out the individual runners and enter the collector. It’s at this point that it creates a vacuum-like effect on the runners, assisting the exhaust gases to escape from the other cylinders. This constant scavenging helps improve exhaust flow dramatically, especially when you start making power over 400 Whp.

You can learn more about exhaust Scavenging in our Blog that dives deep into it and shows examples comparing our Exhaust Manifold to OEM!

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What it takes to Make 500 Whp In Your Mazdaspeed
CS Exhaust Manifold vs The OEM Manifold

When you replace both the Intake and Exhaust Manifolds with a performance unit you are drastically helping your motor improve its efficiency, which can mean 3 things.

1. Make the same power on less boost.
2. Make more power on the same boost.
3. Make Way more power on way more boost. 

When you have to push your car less to make the power you want, reliability improves, and it also needs more room on the table for when you want to make even more power later on.  That leads us to our next topic, Efficiency Mods.

The Cherry On Top 

With a built motor, full bolt-ons, fuel, and a big enough turbo you can easily hit 500 whp.

However, efficiency mods such as Camshafts or Throttle Body will help you make more power easier, or really push the limits of your turbo by improving its ability to perform.

Our CS Camshafts are ideal when you start getting into this power range. It helps with everything from turbo spool, midrange power, and top end. Even on K04 powered speed 3’s / 6’s our cams netted around 20 Whp. You can imagine the kind of exponential improvements it can make as you move up in power.

Camshafts for Mazaspeed
Mazdaspeed Camshafts for DISI MZR Motor

That being said, if you’re already having a motor built, or you happen to be going inside your motor, its not a bad idea at all to toss these cams in. They will only help you, and if anything, help your car to not need to work so hard when you’re pushing its limits.

Performance throttle body for Mazdaspeed
Performance Throttle Body for 2006-2013 DISI MZR Mazdaspeed

To top that off something like our CorkSport Throttle Body has been proven to make more horsepower and flow 33% more CFM than the OEM unit. Up until recently, no other throttle body has been a viable option due to drivability issues. But CS now offers a drop in plug and play unit that doesn’t come with the problems and utilizes OEM ECU logic to function. Modifications like the throttle body are the awesome little bonuses you can do to help the car hit that 500 Whp mark even easier.

Let’s Recap

So, to cover everything that we’ve learned:
This is what we recommend to achieve 500 WHP

1. Built Motor with upgraded Cam Shafts
2. Auxiliary Fueling
3. Full Bolt-Ons, CS Throttle Body recommended.
4. CST5 Turbocharger
5. Manifolds

We hope you enjoyed reading this blog, and now have a better understanding of the details that go into making 500 whp. Next, we will be reviewing the in’s and out’s of 600 whp!

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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.  

Mazdaspeed Cast Exhaust Manifold
CorkSport

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

Those are great questions and 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 Cast Exhaust Manifold
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.  

Mazdaspeed Cast Exhaust Manifold modling in CAD
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Following up is the Design of The Exhaust Manifold

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.  

Mazdaspeed Cast Exhaust Manifold airflow modling
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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 Cast Exhaust Manifold 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!

Installed Mazdaspeed Cast Exhaust Manifold
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.  

Full product Mazdaspeed Cast Exhaust Manifold
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? 

Dynograph of the Mazdaspeed Cast Exhaust Manifold on CST4 Mazdaspeed Turbo
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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.  

Mazdaspeed with CST6 Turbo and Cast Exhaust Manifold Dynograph
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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 Mazdaspeed CST6 Turbo. 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 Cast Exhaust Manifold with TIAL
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 Turbo, 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

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Mazdaspeed 3 Exhaust Manifold Break Down

Today we want to break down the OEM exhaust manifold for the Mazdaspeed platform so that you can better understand how and why the CorkSport Manifold makes power.  

If you haven’t heard, CorkSport has been developing a performance cast exhaust manifold for the Mazdaspeed platform.  We’ve tested and validated samples on Mazdaspeeds ranging from 350whp to 684whp. We’ve done dyno testing on the OEM exhaust manifold vs the CS manifold, as well as on the XS Power V3 manifold vs the CS manifold with the man, Will Dawson of Purple Drank Tuning, setting the calibrations. Both tests showed good gains from just the CorkSport Exhaust Manifold alone.   However, we can get into those details later.  

Mazda Exhaust Manifold Design

Mazdaspeed Exhaust Manifold Flange
OEM Exhaust Manifold Flange

This is the OEM (original equipment manufacturer) exhaust manifold found on the 2007-2013 Mazdaspeed 3 and 2006-2007 Mazdaspeed 6.  Manufactured from cast iron and very compact in design, the OEM design leaves A LOT on the table in the performance department.   

In the image, we’ve labeled each cylinder since that will be important for later discussion.  

OEM Manifold Exhaust Flow

So now let’s talk flow.  Fluids (or exhaust gases in this situation), will always take the path of least resistance.  When the flow path is not clearly defined for the exhaust gas, such as a merge between different cylinders, turbulence is created which reduces the efficiency of the exhaust manifold. 

A prime example of turbulence is shown in the image above with the orange arrows at the merge for cylinder 1 and cylinder 2.  Cylinder 2 comes to a “T” and therefore could flow left or right.  This creates turbulence which causes a loss in potential power.  

Next is the yellow arrow.  This is identifying the inner diameter of the runners in the OEM exhaust manifold.  To our surprise, the inner diameter of the OEM exhaust manifold is actually pretty decent at ~1.48 inches.  This diameter partially defines the power a manifold can support efficiently. Bigger is better in this situation, but small changes here will make big differences in the final performance. 

Surprisingly, there are “performance” exhaust manifolds on the market for the Mazdaspeed platform that have smaller inner diameter runners… 

Mazdaspeed Exhaust Manifold Gasket
OEM Exhaust Manifold Gasket

We also wanted to point out an unusual but important aspect of the Mazdaspeed exhaust manifold and gasket.  Have you ever noticed the seemingly useless extend flange off of cylinder 4? This extended flange acts as part of the passage for the exhaust gas recirculation port.  

You can more clearly see this port path in the gasket.  

OEM  Exhaust Manifold
OEM Exhaust Manifold

Designing For Efficiency

In this image, we want to direct your attention to a very unique and troubling design feature of the OEM exhaust manifold.  There is a right way and wrong way to pair cylinders on an exhaust manifold for a 4 cylinder engine… and this is the wrong way. 

Referencing our cylinder callouts in the first image above; you can see that the OEM design pair cylinder 1 & 2 together and cylinder 3 & 4 together.  This design physically works, but it is not ideal from a performance standpoint. In a divided manifold you should pair cylinders 1 & 4 together and cylinders 2 & 3 together for optimal cylinder exhaust gas scavenging. To learn more about exhaust scavenging you can check out a blog on that here, or watch the video below!

Exhaust Gas Scavenging. See the difference between the CS and OEM Manifolds.

Before we wrap here we do have one good thing to say about the OEM exhaust manifold.  It does sound really good and gives the Mazdaspeed platform a unique exhaust note, but don’t worry you don’t lose your unique rumble with the CorkSport design.   

Thanks for checking in with CorkSport Mazda Performance.  Stay tuned for more info about the CorkSport Performance Exhaust Manifold.  

-Barett @ CS

Exhaust Scavenging Designed with The Exhaust Manifold for Mazdaspeed

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

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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

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Performance Turbo Exhaust Manifolds – Tubular or Cast?

If you have been in the car scene for a while, you have probably seen or heard of performance exhaust manifolds.  Like any other component on the engine that affects flow, performance exhaust manifolds can have a significant improvement to the engine’s peak performance and power under the curve amongst other aspects that the exhaust manifold can affect.  

You have also probably asked the question. “What type of exhaust manifold do I need?” In this blog, we at CorkSport would like to help you better understand the differences between cast and tubular so you can make the best decision for your Mazdaspeed.  

There are two main styles of performance exhaust manifolds; tubular and cast. Both have their pros and cons to consider as an end user (that’s you the enthusiast) and as the designer/manufacturer (that’s us at CorkSport).   

First, let’s look at tubular as it’s the most common in the performance industry.  Tubular is the most popular option because of its manufacturing flexibility.  Unlike casting, tubular does not require expensive molds to develop even a single prototype. Not needing expensive molds allow great flexibility in design and manufacturing, which lends the tubular manifold as an exceptional option for one-off builds.  

Prototype Mazdaspeed Exhaust Manifold tubular installed

To fabricate a tubular exhaust manifold you need just the raw components: flanges, tubular sections, collector and fabrication supplies, and of course the expertise to fabricate the manifold.  Let me emphasize the necessity of fabrication skills here. To produce a reliable and performance-proven tubular exhaust manifold takes the correct skills, tools, and patience…it’s honestly a work of art.  

Exhaust Manifold development for the Mazdaspeed with a tublar design

With this work of art does come some compromises.  To create the necessary runner routing, many tubular sections will need to be welded together.  This increases the chance for weld impurities and slag which can later result in cracking and poor performance.  Any reputable fabricator should be able to avoid this, but it does come at a premium due to the many man hours that must go into each and every manifold.  

Next up is cast.  Manufacturing via casting provides a different set of opportunities and difficulties to overcome.  The process of casting alone has restrictions that must be considered; such as mold design and molten flow in the casting.  Assuming these issues are overcome, casting can provide unique opportunities for the design to improve reliability, performance, and packaging.  

Cast Exhaust Manifold for the Madaspeed

A well-designed cast exhaust manifold can have great reliability due to its one-piece design.  There are no welded joints that can crack or fail and casting typically has a higher threshold to heat before issues arise.  The wall thickness of the casting can also be defined for the application which can improve strength if the exhaust manifold is the only part supporting the weight of the turbocharger.  

Overall performance can also be affected due to the casting design flexibility with each runner.  Unlike tubular, a cast is not restricted to standard tubular elbows and straits. The runners can bend and change profile as desired to aid in performance and packaging.  

CAD design of the Mazdaspeed cast manifold

Speaking of packaging, casting can really change the game here.  Since each runner does not have to be accessible for welding, the entire design and each runner can be tightly packaged together to reduce the overall size of the exhaust manifold and better retain heat which aids with turbocharger response.  

Mazdaspeed Tial with Exhaust Manifold model

Lastly, comes the cost to you the enthusiast.  Although the upfront cost of a cast manifold can be high, typically the unit cost and necessary man-hours are low which helps keep cost down for you.  

As a designer and manufacturer of performance parts for you Mazdaspeed, these are all things we have to consider providing you with the best parts possible.  We’ve explored both and are happy to stick with casting as we feel it provides the best balance reliability, cost, and performance. Keep a look out for future projects and updates!

Thanks for tuning in with CorkSport.

-Barett @ CS

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