ADD W1

Crankcase Ventilation Check Valve

$13.99

SKU: ot-cv-9mm

In Stock
In Stock
Ships by Sep 9
Free Shipping over $200
$100 Minimum Order
30 Days Return

Description

The ADD W1 Check Valve is engineered to enhance your vehicle's crankcase ventilation system by preventing backflow and stabilizing pressure. This patented component is essential for any oil catch can setup, offering crucial protection, especially for turbocharged or supercharged engines. The product is available in two main options: Standard and PRO. The Standard Check Valve is designed exclusively for Naturally Aspirated (NA) engines and provides basic one-way airflow control. It is explicitly not compatible with turbo or supercharged systems. The PRO Check Valve is the recommended upgrade, required for Turbo & Supercharged engines, and supports high boost applications up to 100 PSI. It is also ideal for heavily modified performance builds and is compatible with NA engines for improved performance and reliability. Each kit includes one aluminum check valve (Standard or PRO) and two worm gear clamps, featuring durable anodized aluminum construction. The check valve can be installed on the outlet side of an oil catch can or inline with vacuum or boost lines to prevent reverse airflow. The valve opens in the forward direction at just 0.25 PSI and blocks pressure in reverse. Compatibility extends to ADD W1 catch cans (V1, V2, V3) and other aftermarket catch cans, making it ideal for turbocharged, supercharged, and modified engines. For any vehicle running boost, the PRO Check Valve upgrade is mandatory to prevent crankcase pressure issues and ensure long-term engine reliability.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandADD W1
Part Numberot-cv-9mm
CategoryAir and Fuel

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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