Mishimoto Oil Catch Can: Focus RS Aftermarket Spotlight

Mishimoto R&D of the Catch Can (Photo Mishimoto)
Mishimoto R&D of the Catch Can (Photo Mishimoto) /

We take a look at the newly released Mishimoto Baffled Oil Catch Can and see if this simple upgrade makes a difference in keeping the oil separated in the Focus RS. 

I have to admit; I am pretty excited about the aftermarket cooling products that the team over at Mishimoto is developing for the Focus RS. Every time I click on their engineering blog, it seems like there is a new product being developed! Team “Mishi” has been hard at work making this car even cooler than it is.

Last month, we talked about all the R&D that was going down at Team “Mishi” for the RS. After countless hours of testing, the wait is finally over! The first product on the list: The Mishimoto Baffled Oil Catch Can.

Now I know you might be thinking, why release the catch can first? Why don’t they go big and release an intercooler? But this is exactly why I like the way this development team thinks.

More from Car News

The team about at Mishimoto know a thing or two about the importance of keeping a vehicle cool, especially when it comes to high-performance vehicles. And they know that it takes the proper placement of these parts in a systematic order to achieve greater success.

So does the Focus RS need an oil catch can? Wouldn’t the engineers at Ford Performance have put one in, if it was needed? This is actually a highly debated topic.

I left it to the engineering team at Mishimoto to explain. And it all comes down to a nice little term called “blow-by”.

What is blow-by?

Mishimoto Catch Can Installed (Photo FocusRS.org) /

"“Blow-by is the unburnt oil and fuel mixture that blows past the piston and into the crankcase. Moden engines have a CCV (Crank Case Ventilation) system for emissions purposes. The CCV directs the blow-by back into the intake to be burned in the combustion chamber. Unfortunately, on its way back into the engine, blow-by leaves a nice oily coating on the intake tract, throttle body, and valves.The CCV system is good for the environment, but not ideal for engines. Catch-cans, if used properly, are both environmentally and engine friendly. The catch can will be installed in the PCV (positive crankcase ventilation) line, which is notorious for carrying oil back into the intake system. By interfering with our catch can, we trap the excess oil in the can and send fresh air back into the intake.”"

Makes sense, right? In caveman terms, just remember this: “oily coating in the intake track is bad!

Once Mishimoto finished designing and installing the new oil catch can on their RS, the team spend a good amount of time testing the new system under a variety of different driving conditions.

So what were the results?

The full results can be found on the engineer’s blog here, but long story short, the Mishimoto compact baffled oil catch can found oil buildup in both the hose leading to the catch can, and inside the can itself.

After about 1,000 miles, Team “Mishi” was averaged about 5ml of oil in the can. That to me is enough oil accumulation to justify purchasing this product. As an RS owner myself, I plan on driving this vehicle til the wheels fall off, so to me, its a no-brainer. Because I also have plans for future performance upgrades, the oil catch can will ensure I am keeping my intake tract free of excess oil.

Next: Ford Focus RS: Mishimoto Makes This Car Very Cool

What do you think? It is worth starting your build with the peace of mind that your oil is being properly separated? Hit us up on Twitter and let us know.

Be sure to keep an eye out for our install review of the new Mishimoto oil catch can. For more information on the entire lineup of Mishimoto products being released for the Focus RS, check out the official Mishimoto Engineering Blog here.