Description
The PolarStar Fusion Engine low-flow poppet valve is a component that controls airflow within the Fusion Engine™ system. The valve is available in different restriction levels that either limit or maximize the amount of air passing through the barrel. By adjusting the airflow, you can reduce air consumption or adjust the system’s muzzle velocity depending on the type of valve you choose.
The Red Low Flow valve is a mid-level restriction valve that offers a good balance of power and efficiency.
O-rings
| 1x | M2.0 x 19.0 (Buna 70) - Poppet Retainer |
| 1x | M1.5 x 15.0 (Buna 70) - Poppet Sail |
| 1x | 011 (Buna 70) - Poppet Seat |
| 1x | 011 (Buna 90) - Poppet Base |
How does the poppet valve work?
The standard black valve in the Fusion Engine™ provides maximum airflow through the system, and the nozzle restricts the flow into the barrel, which affects the gun’s muzzle velocity. This gives the gun a wide velocity adjustment range simply by changing the nozzle. With the black poppet valve, you can adjust the velocity range by swapping the nozzle alone.
The Low Flow valve does exactly what its name suggests—it restricts the airflow passing through the valve. As a result, the flow restriction point that affects the gun’s power moves from the nozzle to the poppet valve inside the system. Normally, the nozzle acts as the restriction point, and air accumulates in the space between the valve and the nozzle, from where it flows into the barrel at the rate allowed by the nozzle channel. If a more restrictive nozzle is needed to keep the gun within field velocity limits, pressurized air remains trapped between the poppet valve and the nozzle after the valve closes and the BB exits the barrel. This leftover air is wasted and unnecessarily empties the air tank. The poppet valve’s position is controlled by the Fusion Engine’s second solenoid. When the poppet valve becomes the main restriction point instead of the nozzle, air consumption is reduced because less air is released through the valve at once.
The Low Flow valve also helps improve the consistency of airflow through the barrel, as the air has time to expand slightly in the system after passing through the valve. This reduces turbulence behind the BB, which can slightly improve accuracy. The nozzle does not restrict the flow as much when the poppet valve is the main restrictor. However, the nozzle can still limit airflow if the incoming flow exceeds what the nozzle can pass at once. For this reason, it is generally recommended to use a high-flow black, silver, or red nozzle with the Low Flow poppet valve. When the red Low Flow valve is installed together with these higher-flow nozzles, the Fusion Engine can achieve up to 50% better air efficiency compared to the standard version while producing the same muzzle energy for the BB.
The red Low Flow valve allows an airsoft gun to be optimized for the best efficiency within tuning limits. While it may not reach the same maximum muzzle velocity as the standard valve, it can still meet the velocity limits for full-auto and DMR builds with better efficiency.
Here are examples of how the red Low Flow valve affects muzzle velocity. Tests were conducted at 80 psi and 120 psi using a VFC M4 rifle with a standard hop-up and a 6.05x380 mm barrel.
| Red Nozzle | 400fps - 485fps w/ .20g | 355fps - 415fps w/ .32g |
| Silver Nozzle | 390fps - 450fps w/ .20g | 340fps - 390fps w/ .32g |
| Black Nozzle | 370fps - 430fps w/ .20g | 325fps - 375fps w/ .32g |
https://www.youtube.com/watch?v=5rrpN1OcD64
