PRL Motorsports 2017–2021 Honda Civic Type R FK8 Helix Air Oil Separator
Modern turbocharged engines recirculate crankcase blow-by gases back into the intake tract via the factory PCV system. While effective for emissions compliance, this method also introduces oil vapor, fuel, and moisture, which accumulate in the intake manifold over time. These impurities promote carbon buildup on intake valves, reduce the effective octane rating of the fuel, and contribute to an increased risk of engine knock.
The PRL Helix Air Oil Separator removes these impurities before they are reintroduced into the intake system, helping to maintain a clean intake path and support stable engine operation, all while preserving the factory driving experience.
At the heart of the new PRL AOS (Air Oil Separator) is a proprietary internal helix that generates controlled centrifugal motion within the canister. As blow-by gases enter the system, heavier oil particles, fuel, and moisture are forced outward by centrifugal force, adhering to the canister walls and settling at the bottom. The purified air is then returned to the intake system, maintaining a closed-loop operation and ensuring proper fueling behavior. This system is fully serviceable and requires periodic draining. Maintenance frequency depends on climate and driving conditions.
Every PRL Helix AOS is designed and manufactured in-house, utilizing CNC-machined 6061-T6 billet aluminum with a durable hard-anodized finish. Canisters are available in black or silver anodized finishes and are supplied as a kit with a laser-cut and CNC-bent 304 stainless steel bracket. Custom-molded reinforced rubber hoses, billet aluminum fittings, a billet check valve, and Viton O-rings are used throughout for long-term durability and chemical resistance, allowing for a clean, factory-like installation that complements the FK8 engine bay.
CNC-machined 6061-T6 billet aluminum canister (hard-anodized finish)
Black or silver anodized options
Proprietary internal helix separation mechanism
Custom billet aluminum fittings and billet check valve
Excellent durability and chemical resistance via Viton O-rings
NBR reinforced rubber hoses
304 stainless steel laser-cut & CNC-bent bracket
Maintains a closed-loop system, with no impact on emissions equipment
Vehicle Compatibility
- 2017–2021 Honda Civic Type R FK8
Kit Contents
- PRL Helix Air Oil Separator canister
- Stainless steel mounting bracket
- Custom-molded hose set
- Billet fittings & check valve
- All necessary clamps and mounting hardware
Installation Guide
Before Placing Your Order
〇Import Consumption Tax
At our shopping site, we cover the import consumption tax incurred at the time of import on your behalf, so there will be no additional charges beyond the total amount paid at checkout.
〇Compatibility Check
Our entire product database is based on North American specification vehicles (USDM). Please confirm whether or not the product can be installed on Japanese specification vehicles (JDM) before ordering. (If you are unsure whether the listed product is compatible with your vehicle, please feel free to contact us. Our support team will be happy to investigate for you.)
If you order without confirming compatibility, we cannot accept returns due to incompatibility.
Please note that even if products are sorted by selecting the year, manufacturer, and vehicle model in the tabs on our top page, it does not necessarily guarantee that they will fit Japanese models without modification.
All products have been translated into Japanese using translation software. There may be confusing expressions, so please contact us before ordering if you have any questions.
○Shipping Information
Shipping costs are paid at the time of settlement. An estimate for shipping can be calculated automatically by entering your shipping address on the checkout page. For large items such as body parts, there may occasionally be a significant discrepancy between the automatically calculated shipping cost and the actual cost. In such cases, we will contact you individually via email.
All products are generally shipped internationally from our U.S. warehouse. Unlike domestic shipping in Japan, international shipping takes approximately 7 to 14 days, so please allow ample time when ordering. If you are in a hurry, please contact us in advance to confirm delivery times. Note that all products are transported by air. They will not be shipped by sea freight.
○Regarding Japanese Vehicle Inspection (Shaken) Compatibility
Generally, all products we handle are designed and manufactured outside of Japan. Please note that they are not compliant with the "Japanese Vehicle Inspection System," and we cannot provide strength calculation documents or similar paperwork for these requirements. Therefore, all parts are sold for the purpose of "use on circuits, private property, or off-road," and installation and use are at your own risk.
○Warranty
Please inspect the contents immediately upon arrival. As all products are shipped internationally from outside Japan, there is a possibility of shipping damage to the packaging or the product itself. Please understand that we will only provide returns, refunds, or exchanges for defective products, incorrect items, or products damaged during shipping if you contact us within 7 days of receipt. Furthermore, for products sold through us, warranty support will be provided "exclusively through us." Please note that we do not handle warranty support through other companies or distributors based in Japan.