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Hood Scoop Air Duct Kit

These hood scoop air ducts (aka "air splitters") have a larger opening in order to allow the full intercooler core to be utilized when fitting a larger intercooler to the WRX (such as factory STI IC). They are also taller in height and designed to direct and distribute larger air flows through the big STI hood scoop to the intercooler.

Air duct kits are Spec C aluminum type with single location for an IC water spray nozzle. Kit includes air duct and intercooler seal (aka "bellows"). Intercooler seal clips are sold separately.

Usually ships within 2 to 3 days.

Manufacturer: Subaru


  • Subaru Impreza WRX MY01-07 (Upgrade)
  • Subaru Impreza STI MY01-07 (Replacement)

What is the advantage of using this product? The height of the duct is taller to take advantage of the tall STI hood scoops and increase the air flow across the intercooler core in order to increase its efficiency. Additionally, the area of the opening is increased to match the larger core sizes of the STI intercoolers. By sealing the hood scoop duct to the full dimensions of the intercooler core it ensures nearly all the air passing through the hood scoop will be directed across the core and maximum cooling efficiency will be obtained. If you were to use these ducts with a smaller WRX intercooler the opening will overlap the intercooler core and part of the air flow from the hood scoop will go around the intercooler core rather than through it.

What material is the air duct made from? Aluminum.

Can these be used with the WRX hood scoops? On Version 7 and 8 models (MY02-05) the height of the duct is too tall to fit beneath the WRX hood scoop without modification. On Version 9 models the WRX and STI use the same size hood scoop.

Specifically what intercoolers will these ducts work with? In terms of factory intercoolers, they are designed to work with the STI intercoolers. Yes, there is some variation in the sizing of the STI intercooler cores between JDM and USDM models and across the model years, however, the ducts will work reasonably well with all of them. Aftermarket top mounted intercoolers vary dramatically in size, height, and location within the engine bay so we cannot know how the fitment will be.

Do I need to buy intercooler seal clips? The rubber seal (or bellows as it is sometimes called) attaches to the air duct with plactic clips. The clips on your original air duct are the same between WRX and STI and can be re-used, however, the STI seal being a little longer requires an additional two clips on Ver.7 and 8 models.

On Version 7 models what is the difference between the regular STI air duct and the Spec C version? The regular STI air duct is made of steel while the Spec C version is aluminum. Additionally, the MY2001 STI air duct accomodates 2 IC water spray nozzles, while MY2002 STI and the Spec C ducts accomodate only 1 centrally mounted nozzle.

Is it possible to install the V7 kit on a MY04-05 WRX with the shorter WRX hood scoop? Some customers have indicated that it is possible to do so but we have not actually verified it ourselves.