On this page, you are looking at the Tial Q Blow Off Valve. This blow-off valve delivers in performance for vehicles from mid to high horsepower levels to relieve boost.
Here are the details:
The spring pressure in the valve does not correlate with the amount of boost pressure you want to run. The size spring you need is determined by your engine vacuum at idle. Please refer to the charge below to select the right pressure for you.ENGINE VACUUM READING SPRING COLOR SPRING RATE -22 and -23 in/Hg Brown -12 PSI (-24 in/Hg) -20 and -21 in/Hg Yellow -11 PSI (-22 in/Hg) -16 and -19 in/Hg Un-painted -10 PSI (-20 in/Hg) -12 and -15 in/Hg White -8 PSI (-16 in/Hg) -8 and -11 in/Hg Black -6 PSI (-12 in/Hg)