Realspool - not sure what you mean by "feel like a V8" but please quit saying that...you make our cars sound slow
To understand how the Grainger (poppet) valve works, you have to understand how our waste gate system works.
The waste gate is simply an air diaphram contolled "door". When the actuator opens the door, exhaust gas by passes the exhaust turbine on the turbo. This in turn keeps the turbine from spinning any faster. The faster it spins, the more boost is created. Get it?
OK - now, Not only how much but, WHEN the door (waste gate) opens is important...the grainger valve can control the WHEN.
Look at it this way -
How much it opens = how much boost
Grainger valve = WHEN it starts to open (quicker spool).
The wastegate actuator is simply a spring tensioned rod setup. when pressurized air is fed into it, the air diaphram will overcome the strenth of the spring and the door will start opening (rod will start moving). This starts to happen at a relativly low pressure (under 5lbs) Then the door will creep open more and more as pressure goes up to your set point. It's the initial low pressure opening that needs to be delayed...this will increase spool because exhaust gas is not being leaked off as early...
Insert a Grainger (poppet) valve and you can delay that initial pressure opening point.
A Grainger valve will not allow pressure to go through it until a specified pressure. It actually works on the same theory as our wastegate actuator. There's a diaphram inside with spring tension. When the air pressure over comes the strength of the spring, it opens and allows the air through. The advantage to this is the wastegate door will be held tightly closed instead of slowly creeping open until your setpoint...this will help with quicker spool.
