RE: Head-to-Head Comparison: 2008 Shelby GT500 Mustang vs. 2008 Challenger SRT8
[quote]ORIGINAL: RLSH700
A mechanic told me about this. They have alternate valve routes for this. Superchargers work kind of like MDS systems, they provide power on demand or in this case boost on demand. The supercharged cars I have ridden in and driven will have no boost if your feathering it or cruising. It isn't until you press for it to engage. Although the engine is spinning the pulley at all times, it isn't really doing anything until the system engages it.
Reply:
On the belt driven chargers there is a relief valve that simply doesn't allow any boost until the PCM sees a certain throttle angle. The supercharger is just "freewheeling". When the PCM shuts the valve this allows the charger to build boost to whatever level is intended. Unlike Mel Gibson in "The Road Warrior" I haven't seen anything where the belt can be stopped and started with a switch,lol. A lot of the rice rockets have a "blow off" valve which is essentially the samething and operates in the same manner only it is allowed to have an audible "hiss" when relieving pressure. These are turbocharged but also must have a way to relieve pressure so the turbo isn't damaged.