CorkSport Throttle Body Spacer

We are proud to introduce the CorkSport 72mm Throttle Body Spacer for Mazdaspeed 3, Mazdaspeed 6, and Mazda CX-7 Turbo.

This is a great product for those Mazdaspeed owners who want push past the limits of their OEM fuel system. We’ve carefully chosen nozzle locations, upgraded the inside diameter, and added an O-ring for quick and easy sealing. We designed the CS throttle body spacer to eliminate a lot of the headaches that come with adding extra fuel.

The area where the throttle body mounts is pretty tight on the Mazdaspeeds which leaves few options for adding methanol nozzles, especially the tall AEM ones. We realized right away that nozzle orientation was critical.

To prevent any modification, the top nozzle location sits at an angle that perfectly clears both the OEM & CorkSport Intake Manifold to provide an access port for most meth nozzle styles on the market. For more stealthy setups, there are two ports located on the bottom side of the CS spacer, one straight down and once again at an angle for easy usability without further modification.

We also considered nozzle depth when designing the CorkSport Throttle Body Spacer. Most nozzle styles will sit flush to the inside surface of the spacer. This prevents any irregular airflow around the nozzle locations without affecting the spray pattern of the nozzles.

Just like the CorkSport Performance Throttle Body, we enlarged the inner diameter of the throttle body spacer to 72mm. This is the maximum size that can be used with the OEM bolt pattern and ensures optimal best airflow. The OEM throttle body & gasket can still be used with no issues.

Each CorkSport Throttle Body Spacer is precision machined from 6061-T6 aluminum before being anodized black for a clean and durable look. An O-ring groove is added during machining to allow the spacer proper sealing to your intake manifold. Rest assured, the O-ring is safe with all fuels and even oil. Finally, the spacers are laser etched with a CorkSport logo for a subtle finishing touch. The entire package is wrapped up with hardware; including extended length throttle body mounting bolts & two NPT plugs for the nozzle/injector ports you are not using.

If you’re running out of fuel in your Speed and we can make installing a methanol system much easier, pick up a CorkSport Throttle Body Spacer.

Auxiliary Methanol Fueling for Your Mazdaspeed

The Mazdaspeed platform is a great place to start if you’re looking for a fun tuner car that offers awesome power to money spent ratio.  This holds true until you hit the capacity of the OEM fuel system. If you don’t know it already, the DISI MZR was one of the first gasoline direct injected engines offered in a passenger car.  For its time, the Mazdaspeed was a powerful and capable sport hatch right off the showroom floor, however, this type of fuel system quickly reaches it’s limits and is not easily modified for higher power.  

In this blog, we are going to take a look at auxiliary fueling with methanol and my personal experience taking this path.  

Damn, I’m out of fuel…  You got your Speed setup with all the hard parts (aka fully bolted) and finally pulled the trigger on that big turbo.  Just a few revisions and your tuner is telling you you’re out of fuel and more or less stuck at around 350-380whp (depending on turbo and octane).  It’s time for auxiliary fueling.

Now when considering auxiliary fueling it is critical to consider your goals with the car; the level of complexity and cost are drastically different depending on these goals.  

380-440whp Goal:

With this power goal you most likely have a fully bolted Mazdaspeed and an upgraded turbo such as the CorkSport 18G.  To achieve this power the auxiliary fuel system can be fairly simple.  From my experience, a single nozzle with the appropriate flow rate positioned just before the throttle body can get the job done.  This setup is very simple, consisting of a progressive rate controller, fuel cell, some tubing, nozzle and ideally a check valve on the nozzle.  This will cost you around $450 to get started.

I personally started with the AEM Methanol Kit, but there are many other kits available such as Devil’s Own, Auqamist, Snow Performance, and ProMeth.  I recommend doing some research to find the best kit for your needs before jumping in.

440-500whp Goal:

Once you break past that ~440whp mark you should really start to consider adding nozzles.  There’s a couple ways to do this.

First, you could maintain your basic system by adding another nozzle with a splitter and another port in your intercooler piping, just before the throttle body.  This can get you close the 500whp mark but is not ideal as you will need to run two very large nozzles. With nozzles, this large the fuel has difficulty atomizing and instead can condense into relatively larger droplets.  This is not ideal; however is only the added cost of a splitter and nozzle.

The other option is running a single nozzle on each intake manifold runner.  Check it out below.

By doing this, you can now run a smaller nozzle that will atomize much better, but since you have four nozzles you can still flow the appropriate volume for your power goal.  However, with this nozzle location, we have made a drastic design change to the system. In a pre-throttle body set up the nozzle never see vacuum, however once located in the intake manifold they will see vacuum which requires additional components to operate correctly.  

To avoid the risk of hydro-locking your engine and awful driving characteristics, we must add a check valve to each nozzle and a solenoid controlled valve to the hose that feeds the nozzles.  Check valves (which you see a close up of in just a bit) allow fuel to flow in only one direction. Along with that, a properly design check valve will have a crack pressure (minimum pressure to allow flow) that is slightly greater than the vacuum force in the intake manifold.  A solenoid is a valve that opens and closes and is controlled by the controller. This allows fuel to flow only when commanded by the controller.

Let’s take a closer look at the nozzles and distribution block necessary for a per-runner nozzle setup.  Looking at the nozzles you’ll see silver cylinder between the nozzle and the black fitting that connects to the hose.  This is the check valve. A simple, but critical part of the system for proper function. Up towards the top of the image, you see a single hose entering a black block along with four separate hoses leaving the block to each nozzle.  This is the distribution block; this can be configured in many ways, but more or less it allows you to direct fuel to each nozzle from a single hose.

So, as you can see moving to a per-runner setup includes a lot more complexity and cost.  This added cost is approximately $300 on top of the methanol kit you already purchased and not including an intake manifold that is already set up for nozzles.  You could cut a little cost by using nylon tubing versus stainless braided hose, but not much.

It’s also worth noting that the pump that comes standard with most kits will not flow enough fuel to support just under 500whp, so depending on your goal you may need an upgraded pump as well.  If this is the case I would recommend the pump from ProMeth only because it’s the only pump I’ve found that truly flows more.

500+whp Goal:

At this point, I would simply recommend moving to a true port-injection system.  Like the per-runner nozzle setup, a true port injection setup sprays fuel in each runner, but the systems, in general, are very different.  Since port injection alone could be a couple blogs on its own I will give the quick and dirty here. A true port injection setup uses conventional style gasoline injectors that control flow amount directly in the injector itself.  This allows much more precise control and reduces a lot of risks. However, the cost is much higher starting around $1500-$2000.

Lastly, I wanted to mention some things I love about using methanol for auxiliary fueling.  Methanol is expensive, about $8-$12 per gallon which is a real bummer, but it does not get used for all driving situations.  You don’t use the methanol unless you are pushing your car to the point that the extra fuel is needed.

The methanol is contained in a separate fuel cell like the image above verses in the OE fuel tank.  Therefore it’s only used when you want to use it. Unlike E85 blends or other exotic fuel that must be mixed and/or used through the standard OE injectors and therefore used for all your commuting.  

I hope my lessons learned were useful for you and your exploration into methanol auxiliary fueling.   With that, I sign off.

-Barett @ CS

*All pricing based off of price at the time of the blog writing.