Tial is the #1 faked brand in our entire industry. 
Do NOT purchase a Tial BOV or Wastegate from an untrusted source (random ebay seller, some guy on Facebook, a website who is not an authorized Tial dealer (WE ARE - call Tial to confirm!), etc).
If the price is too good to be true - there's always a reason.  Fake Tial BOV's and W/G's are made in China and will leak from day one, they are complete junk.


How do you know what spring to choose?  Its based on your vacuum at idle.  If your car doesn't currently start, contact us and we can generally recommend the correct PSI for your application.  For example, most MKIV Supras need an 11psi spring, but some need a 10 or 12psi spring.

Assuming your car starts - use this chart to determine what spring you need.  Make sure you're looking at the Q (ASSEMBLY DESIGNATION).

According to Tial, the new Q Bov vents 60% more air than the original Tial 50mm BOV.

Blow Off Valves are an essential part of any turbocharged powerplant. When a turbo system is making boost, then the throttle closes, the turbo will go into a backspin condition without a blow off valve. This will eventually kill the turbo. Another concern for a BOV is that it can hold boost without leaking under wide open throttle conditions. This Tial Q BOV does an excellent job of completely venting the system, but not leaking under load.

Q is the first revision of the original TiAL BOV. The Q bolts up to any standard TiAL flange, no re-welding. This is the highest flowing BOV on the market. It's offered with a variety of springs for different vacuum levels and a special spring specifically for supercharged vehicles

Features:

• For use on turbo-charged and super-charged applications (Paxton, Vortec, etc.). The body and all internal components are CNC-machined from 6061 aluminum alloy. It features a large 1.98 in (50.5mm) valve.
• The V-Band design aluminum mounting clamp gives a very clean and unique appearance. The clamp uses Stainless Steel hardware for a long lasting, corrosion-free appearance.
• The valve seal utilizes a Viton O-ring that is clamped in place to prevent the possibility of sticking to the seat and pulling out. The valve stem and guide are Teflon-lubricated, hard anodize-coated for wear resistance.
• The Blow Off Valve also comes with our own machined aluminum banjo-type air fitting and bolt, with over sized 10mm hose barb for quick actuator response. The actuator has a high temp silicone Nomex-reinforced diaphragm for long life.
• An aluminum weld base mounting flange is furnished with each unit. A Mild Steel or Stainless Steel Flange is available at an additional cost. The use of 6061 aluminum allows the housing to be anodized with a selection of colors.
• Through countless hours of R&D we were able to make the same size valve flow a staggering 60% more than the original design - that means 60% more air is blown off per cycle! This is the highest flowing BOV on the market.
• Color anodized aluminum options (Silver, Red, Blue, Purple, Black).
• A single Q BOV can support up to 1,800hp