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Weapon R Secret Weapon Air Filter for 4th Gen Subaru Forester

Universal (Optional Ram Air Kit Only)
More / Larger Pics (1)
Fits:
Universal
Notes:
Optional Ram Air Kit Only
More Info:
This is a Universal application. Please read all notes including the product description to determine if this part will work for you. ONLY includes the ram air kit. DOES NOT include the filter.
List Price:
$67.00
Our Price:
$54.95
You Save:
$12.05
 
 
(shipping rates shown in cart)
Select an Application For Your
4th Gen Subaru Forester
 
Year Range
Door Config  [Trim Level]
Application / Notes
Universal
(2.5" Inlet, 6.5" Wide, 6.5" Tall)
Universal
(2.75" Inlet, 6.5" Wide, 6.5" Tall)
Universal
(3.0" Inlet, 6.5" Wide, 6.5" Tall) (Stealth Black)
Universal
(3.0" Inlet, 6.5" Wide, 6.5" Tall)
Universal
(3.5" Inlet, 6.5" Wide, 6.5" Tall)
Universal
(4.0" Inlet, 6.5" Wide, 6.5" Tall)
Universal
(Optional Ram Air Kit Only)
 
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CARB Compliance / Exemption Warning: If you live in California and your application for this product is not CARB Compliant / Exempt, then you cannot purchase it for public highway or street use (in that case it could only be used for formally sanctioned race use on a racing vehicle that may never be used on a public highway or street). If your application is not CARB Compliant / Exempt and you're shipping to California, our system will let you know on the final checkout page.

This filter, when used with the Ram Air Kit, is great for enhancing any brand short ram intake you might already have. The Secret Weapon Air Filter and Ram Air Kit work together to bring colder, higher velocity air into your intake system!

The Secret Weapon Air Filter is a result of countless hours of testing and tuning of air intake velocity, air mass and air speed. The result is an air filter that performs better than any other air filter available in the market today. The goal of the Secret Weapon Air Filter is to provide maximum airflow, with the protection of high quality dense Polyurethane foam. Many studies have shown flow rates of up to 80% more air and better dirt filtration with foam filters than conventional cotton filter. The Secret Weapon Air Filter's main feature is an CAD designed and flow benched tested Velocity Stack, which greatly increases airflow, air speed and air mass into your engine.

The filtering element of the Secret Weapon Air Filter uses Open Cell Technology, which traps dirt particles entering your engine. Best of all, the Secret Weapon Air Filter will not easily clog because it is 16 times thicker than a traditional cotton filter, and the Open Cell Technology allows air to flow around the captured dirt. Therefore, the Secret Weapon Air Filter will perform great even when it gets dirty.

Key Features:
  • Dense Polyurethane foam filter provides best performance and great dirt filtering.
  • Top inlet provides additional airflow capabilities.
  • The inlet at the top of the filter can also be connected to the Secret Weapon Ram Air Kit to provide additional power gains. To use the Ram Air Kit, simply place one end of the tube on the top inlet of the air filter and the other end in an area that will have get a lot of cold outside air, like behind your front grill or fog light holes.
  • No oil is used in this filter. This means no warranty issues from oil traveling along the inlet and clogging your Subaru Forester's MAF sensor.
  • Performs great even when dirty (does not easily clog).
  • CAD designed and flow bench tested Velocity Stack.
Fitment Notes: Please measure the diameter (where the filter is) of your current intake system before selecting an application. These filters will work with any brand intake system that uses a similar sized filter. Please make sure the inlet size matches the diameter of your current intake system.

Ram Air Kit Notes: The optional Ram Air Kit will ONLY work with Secret Weapon Air Filters. The kit basically consists of a long, flexible tube which you can position anywhere that works best for your setup (most customers will place it so it sucks air from the front grill or fog light holes).

Cleaning Notes: We suggest this air filter should be replaced every 15 to 20 thousand miles, depending on your conditions. Although a cleaning kit is available, we recommend just replacing the filter when it comes time for a cleaning. Even though this method costs a bit more, it ensures you get the best performance out of the filter (oftentimes customers will not use the cleaning kits correctly which can results in decreased performance and filtration abilities, and over-oiling an oiled filter can cause MAF sensor clogging).

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Application
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