⚠️ This BOV is NOT a direct fit for most vehicles.
Installation and use of this product may require modification, fabrication, or additional components such as a charge pipe with the proper flange configuration. Customers are responsible for confirming compatibility prior to ordering this product. All returns require RMA for approval, and approved returns will incur a 10% minimum restocking fee. Outbound shipping is non-refundable.
Routing and plumbing are not included and we do not advise on the installation of this component.
**NOTE: soft spring pressures are recommended for use with Journal Bearing turbos**
For full details, please carefully review the manufacturer's information: TiAL Sport Product Overview
Includes:
- TiAL Q BOV Assembly
- TiAL V-band Clamp
- V-band Weld Flange
- TiAL Air Fitting
- High-Pressure O-ring
How do I decide which springs to use?
Unlike wastegates, spring pack choices for BOV products are made using engine idle negative
pressure, or vacuum, rather than boost pressure. Use a reliable gauge to measure vacuum at idle,
then use the chart published in the Spring Chart Section on this page.
You may also consult with TiAL Sport guidance, here: https://tialsport.com/wp-content/uploads/2022/12/BOV-Static-Testing.pdf
How can I make my BOV louder/quieter?
It is surprising that this question is often very polarizing; some customers want the valve to be
quieter, some want it to be louder. In general, the open body of the Q BOV results in a quieter
discharge with the greatest flow, where the QR BOV discharges at a higher velocity with a reduction in flow and is therefore typically louder when not recirculated. The QRJ, with a very modular outlet design, can configure to discharge to atmosphere or recirculate. Therefore both ‘quieter’ and ‘louder’ operation can be accomplished with one valve.
How do I connect the BOV?
The BOV is designed with an air fitting sized for ¼” (or 6mm) hose. The larger hose allows for quicker response and better control under positive boost pressure. This hose should be connected to full engine vacuum, preferably directly to the intake manifold, without any check valve or “tee” in place. Various routing methods can be seen here: https://tialsport.com/wpcontent/uploads/2024/06/BOV-Routing.pdf
Why is there a unique spring pack for supercharged applications?
Supercharged engines typically produce positive manifold pressure at idle, and most supercharger
manufacturers recommend bypassing that pressure for tuning purposes. As a result, TiAL Sport suggests a very weak spring to allow the valve to remain open at idle, but to close very rapidly once that negative pressure transitions to positive pressure. It is perfectly normal for our BOV to be open at idle on supercharged applications.
