Killer Bee Upper Coolant Reservoir Review


As part of a series of new additions to clean up the engine bay and make it look better, the Killer Bee Upper Coolant Reservoir is a very welcome addition. One of the not-so-nice side effects of the Subaru engine layout is the fact that the turbo coolant hoses actually sit higher than the fill cap on top of the radiator. Traditional vehicles allow you to fill your radiator with coolant right at the radiator. But since the Subaru turbo is elevated above the radiator cap, this setup requires that you have a fill point higher than both the turbo and radiator to prevent any air from entering the system.

The Subaru OEM upper coolant reservoir is large, bulky, and not very pretty. It also sits right in the pathway of your turbo intake with any kind of rotated turbo setup. Many tuners are forced to relocate this reservoir to various places, and its not an easy task.

This is where Killer Bee has made a small innovation that cleans up space and makes for a nicer engine bay.

It’s a fairly straight forward install. All the ports and necessary hookups are right on this tiny reservoir and it bolts right up. It’s hard to even call it a reservoir since it holds almost no coolant. This isn’t a problem since the coolant is a pressurized system, and this only only serves as your fill tank, since its still the highest point in the coolant system.

The Killer Bee Upper Reservoir is a beautiful, solid, single piece of billet aluminum and powder coated black. You reuse your stock radiator cap, since it has a valve in it to bleed off any excess coolant into your overflow tank. Once installed, I needed to fill and “burp” the coolant system to remove air from inside the passages. I had to source a special “spill free” funnel to aid in this process. Once filled, squeeze both upper and lower radiator hoses and try and get as much air passing through the coolant system.

Then let the car run for a few minutes until the radiator fans actually turn, so that the thermostat opens and actually circulates coolant through the radiator. Make sure all the bubbles are gone and then button it up.

Kudos to Killer Bee for making this piece! I know it’s likely not going to be a big seller, but it was a welcome addition to my engine bay!