TiAL® Blow Off Valve Springs are designed to work in all of their blow off valve models including the BV 50mm, Alpha Q, Q and QR valves. You should select the BOV spring pressure rating based on your engine's vacuum reading at idle, once the engine has reached operating temperature. However, the pressure ratings will vary depending on the model blow off valve you have, so please reference the chart below to ensure you are purchasing the correct spring for your application.
| BV
50mm Spring Ratings |
| Green |
3 psi (.21 bar) |
SUPERCHARGERS ONLY |
| Black |
7 psi (.48 bar) |
-8 to -13 inHg |
| White |
9 psi (.62 bar) |
-14 to -17 inHg |
| Un-painted |
11 psi (.76 bar) |
-18 to -20 inHg |
| Yellow |
12 psi (.83 bar) |
-21 to -23 inHg |
| Alpha
Q Spring Ratings |
| Green |
3 psi (.21 bar) |
SUPERCHARGERS ONLY |
| Black |
7 psi (.48 bar) |
-10 to -13 inHg |
| White |
9 psi (.62 bar) |
-14 to -17 inHg |
| Un-painted |
11 psi (.76 bar) |
-18 to -21 inHg |
| Yellow |
12 psi (.83 bar) |
-22 to -23 inHg |
| Q
and QR Spring Ratings |
| Green |
2 psi (.14 bar) |
SUPERCHARGERS ONLY |
| Black |
6 psi (.41 bar) |
-8 to -11 inHg |
| White |
8 psi (.55 bar) |
-12 to -15 inHg |
| Un-painted |
10 psi (.69 bar) |
-16 to -19 inHg |
| Yellow |
11 psi (.76 bar) |
-20 to -21 inHg |
