A Granatelli blow-off valve releases boost pressure when the throttle closes, helping protect your turbocharger from compressor surge. Choose from three 50mm BOVs or the 64mm Anaconda for high-horsepower turbo and centrifugal-supercharger builds. Designed, engineered and tested in Oxnard, California.
Which Granatelli BOV Is Right for You?
| Blow-off valve |
Valve size |
Key details |
Best for |
| 50mm Adjustable Blow Off Valve – 540200 |
50mm |
V-band; +6 and +15 psi springs included |
Most turbo street builds; best value |
| 50mm Ultra High Flow – 540201 |
50mm |
Same 50mm diameter with more room for air to get out |
Builds that need more relief flow in a 50mm package |
| Viper Series – 540198 |
50mm |
Billet aluminum; adjustable spring preload; vent-to-atmosphere |
Turbo street, high-boost, drag and race cars |
| Anaconda – 540199 |
64mm |
Billet 6061 aluminum; atmospheric discharge |
High-horsepower turbo, centrifugal superchargers, large charge piping |
Accessory: Anaconda BOV brass 1/8" NPT pneumatic valve filter (540199-FTG).
Blow-Off Valve FAQ
What does a blow-off valve do?
When you lift off the throttle, boosted air has nowhere to go. The BOV opens and releases that pressure so it doesn't surge back through the turbo's compressor.
Does a blow-off valve add horsepower?
No. A BOV doesn't make power by itself; it protects the turbo and helps the system respond cleanly between shifts and throttle lifts.
50mm or 64mm BOV?
A 50mm valve covers most turbo builds. Step up to the 64mm Anaconda when you're moving a lot of air: high-horsepower turbo setups, centrifugal superchargers and large charge piping.
Is a vent-to-atmosphere BOV OK for my tune?
The Viper and Anaconda vent to atmosphere. Check with your tuner before installing, especially on MAF-based engine management.
Do I need a blow-off valve and a wastegate?
Yes, for most turbo builds: the wastegate controls boost on the exhaust side and the BOV handles the intake side. Read Wastegate vs. Blow-Off Valve or shop Granatelli wastegates.
