MISHIMOTO MMRT-RS-16E
MISHIMOTO MMRT-RS-16E
MISHIMOTO MMRT-RS-16E
MISHIMOTO MMRT-RS-16E
MISHIMOTO MMRT-RS-16E
MISHIMOTO MMRT-RS-16E
MISHIMOTO MMRT-RS-16E
MISHIMOTO MMRT-RS-16E
MISHIMOTO MMRT-RS-16E
MISHIMOTO MMRT-RS-16E
MISHIMOTO MMRT-RS-16E
MISHIMOTO MMRT-RS-16E
MISHIMOTO MMRT-RS-16E

MMRT-RS-16EBK

Mishimoto® (13-18) Ford Focus ST/RS Aluminum Coolant Expansion Tank

Regular price$250.95
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Compatible: (2.0L/2.3L)

2013 - 2018 Ford Focus ST

2016 - 2018 Ford Focus RS


After a few hot and cold cycles, Mishimoto recommends checking the sight tube on the side of the expansion tank to confirm proper coolant level.

 

Add some reliability and engine bay styling to your Focus RS/ST with the Mishimoto RS/ST expansion tank. This tank features internal baffles to prevent coolant starvation from overflow ports on the engine. Also, during high-speed cornering, braking, and acceleration, the internal baffles reduce coolant sloshing. The engineers at Mishimoto have included a sight tube to allow for proper observation of hot and cold coolant levels, making engine maintenance much easier.

Eventually, you’ll have to consider the health of your plastic expansion tank. Plastic is prone to failure after years of constant temperature variations. The Mishimoto tank is constructed from durable, TIG-welded aluminum for optimal durability and longevity. It reuses the stock expansion tank cap and includes an overflow nipple on the fill neck for adding an additional coolant tank so your Focus RS stays NHRA legal. All areas of concern are covered with this upgrade.

It’s worth noting the Focus’s stock tank is an engine bay eye sore, whereas the Mishimoto tank comes in three different variants to help with aesthetic customization: black, wrinkle red, or Wrinkle Nitrous Blue. Each of these options works with both the 2013+ Focus ST and the new 2016–2018 Focus RS. For convenience, you can install your new coolant tank upgrade in under one hour as it was engineered with perfect fitment in mind. Like all our Focus RS parts, this expansion tank also includes the Mishimoto Lifetime Warranty.

  • Direct fit for the 2016–2018 Ford Focus RS / 2013-2018 Ford Focus ST
  • Sight tube allows for proper hot and cold coolant levels
  • Internal baffle keeps coolant near overflow port during aggressive driving, preventing air entry into coolant system
  • 100% aluminum, fully-welded construction for maximum durability during repeated temperature transitions
  • Overflow nipple on fill neck allows for installation of additional NHRA-mandated overflow reservoir
  • Fits with stock overflow tank cap
  • Available in Wrinkle Nitrous Blue, wrinkle red, or black powder-coated finish
  • Mishimoto Lifetime Warranty

 

PURCHASE INCLUDES

(1) Aluminum Expansion Tank w/ Sight Tube
(1) Overflow Hose
(2) Rubber Sleeves
Mishimoto Lifetime Warranty

 

TANK LOVE – COOLANT EXPANSION TANK R&D, PART 1: DESIGN PLANS

The stock cap is has a pressure limit of 21psi
The stock cap on the RS has a pressure limit of 21psi
Expansion tank for the ST
Factory expansion tank for the ST

There is a lot of focus (I haven’t made that pun in a while, give me a break) devoted strictly to improving how this EcoBoost hot-hatch platform performs since it’s introduction. This is important, our engineers have that as a clear goal in their minds. For our RS, we’ve released an oil cooler and a catch can, while an awesome performance intake, a complete intercooler setup, including pipes and a bad*** rear differential cooler are all on the way (see our entire product line for the ST as well). Trust me, we will make our RS fly like a bat-out-of-hell once we’re done with it, but how many products out there add a little bling to this platform? Certain parts may not make you faster, but they can always look better.

Mishimoto cares about making you look good, so this project has moved fast. We have already begun making a 3D model of our tank design and had it 3D printed to test the fitment on our RS (fun fact, it will fit both the RS and any 2013+ ST!). To save time, we printed this entire assembly in pieces. You will notice a line in the middle of the tank, this is where the halves were epoxied together. The fill neck was also printed by itself, and had to be attached to the body of the tank separately. Remember, this isn’t a functional prototype, our engineers just wanted to be sure the design fit. See below.

The underside of the tank showing the feed and return port lines
The underside of the tank showing the feed and return port lines
You can see the horizontal line splitting the two
You can see the horizontal line splitting the two

Another cool thing we are doing with this tank is adding a sight tube. In past expansion tank projects, it hasn’t always been a feature that we could add due to how the design fit the vehicle application. We incorporated a sight tube here so you can tell how much fluid is in the tank without much trouble. There is also internal baffling that will prevent slosh.

The sight tube was printed along with that half of the tank
The sight tube was printed along with that half of the tank

Now that we know the prototype fits, it’s time to get a real, functional prototype into our facility. The good news is that we have a few on the way! I’ll leave you with what this prototype looks like on our shop RS. Just imagine whatever finish you think would work for your ride and you’ll pick up on the complimentary design we are going for!

TANK LOVE – EXPANSION TANK R&D, PART 2: FINAL REVEAL

The stock unit pales in comparison to the size of the Mishimoto tank.
The stock unit pales in comparison to the size of the Mishimoto tank.

One of the first things you’ll notice with this tank is the capacity increase over the stock unit. We are making this tank to fit both the Focus RS and ST, but that doesn’t mean we have to stay within the size parameters of the stock unit. The stock expansion tank holds a maximum of 1.56 liters of fluid. Our design more than doubles that, with a maximum fluid capacity of 3.58 liters. With the increase in capacity comes an increased chance of fluid sloshing inside the tank during hard driving. To combat the extra fluid’s movement, we designed some internal baffling that should keep sloshing at bay.

See the sight tube on the left of the tank?
See the sight tube on the left of the tank?

Another interesting feature we include on this expansion tank is a sight tube attached to the side of the tank. Due to design constraints. it’s not always possible to include something like this in an expansion tank, but it happened to work out nicely in this case. In order to monitor your tank levels, all you need to do is look at the sight tube – easy! So, what does this tank look like installed?

The finish matches with the engine cover
The finish matches with the engine cover

The stock unit on the ST and RS stands out like a sore thumb. Our design, on the other hand, is quite pleasing to look at and almost looks like an OEM part. It’s an improvement from the plastic stock part in two ways: 1) it’s constructed with aluminum; and 2) it doesn’t look like a makeshift experiment with a milk carton. One thing I really like about this finish is how well it matches with the engine bay components. There is a lot of black plastic in the engine bay, and this tank ties everything together. We are car enthusiasts, too, so know you want to feel proud whenever you pop the hood and see a matching engine bay.

Which do you prefer?
Which do you prefer?

Now, I know what you’re thinking: “Didn’t he say it also fits the Focus RS? I’m pretty sure I saw photos of that prototype installed on an RS.” It does! It looks just as good, too. There is absolutely no modification required to fit this tank on the RS, as the mounting points are the exact same between the chassis.

Our new expansion tank fitted on our shop RS
Our new expansion tank fitted on our shop RS

You Spoke, We Listened

Speaking of the RS, have you been following our performance intake development for our Ford Focus RS? We’re always trying to follow along with what car owners of a specific model would probably want to see. Being fans of the Nitrous Blue RS, (and having one as our actual shop car), and keeping our ears open to the MKIII community, we thought it would be cool to have another part to match the color scheme – which is how we came to making a Nitrous Blue intake pipe. Couldn’t we have done that with this product?

Oh yes, yes we did:

May I introduce, the Nitrous Blue Expansion Tank
May I introduce, the Nitrous Blue Expansion Tank

You spoke, and we listened. Due to the popularity of our Nitrous Blue intake pipe, we have gotten so many requests to make this tank in the same color, and we could not ignore them. When the sample arrived at our R&D headquarters, it dropped jaws just like the intake pipe did when we installed that on our shop RS for the first time. Check out some shots of it installed on our RS below:

It matches so perfectly!
It matches so perfectly!
This tank is the same color as our intake pipe
This tank is the same color as our intake pipe

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What do you guys think? Everyone in the office says it looks awesome. This Nitrous Blue (or NB as a lot of you guys like to call it) is so unique when it comes to light sources. The color produces ever so slightly different shades of blue depending on whether it is in natural or artificial light, which is what makes matching this color a bit more challenging than one would expect.

All trials and tribulations put aside, we have completed the development of this project, and we are almost ready to release it into the market. What do you guys think? Do you like the blue? What color would you like to see? Leave a comment below or cast your vote on our forum thread!

 

Install Guide:

 

 

Warranty: