Explaining the Mystery of Subaru Radiator Caps

After we had all of our overheating issues at Super Lap Battle, we got a message from James Hudson from Colonel Red Racing that pointed us to the note on all of Mishimoto's Subaru Radiators.
Specifically, the fact that the Mishimoto cap that comes with their radiator is a 2-way cap, and is not to be used on the radiator. If you put the 2-way cap on the radiator it says, overheating may occur.

This was the first time that all of us here had heard about a 1-way radiator cap vs. a 2-way, so we then went and had to look into what the difference between the two types of caps is, and it was really interesting.

It definitely seems that there is not as much information about the difference between these caps out there as there should be in regards to using them on Subaru's. It would also seem that having incorrect radiator caps on your car may play a part in overheating issues, which could be easily overlooked.

And the other interesting thing is that every aftermarket cap that we could find is a 2-way cap. And if using two 2-way caps on a car can cause issues, that may require some changes to be made.

Thanks for watching and Stay Tuned!

Here is a link to the OEM Subaru 1-way cap on our site if you need one:

https://www.flatironstuning.com/subar...