A supercharger system that is designed for the street needs to have some belt slip to damnpen the shock on the supercharger itself. The bypass valve on a roots type blower at least, only opens when the vehicle is at a constant speed and a vacum is present to improve fuel economy and a few other things. Under WOT the bypass valve remains closed since it will always see boost.

For the slipage you want just a little b/c everytime you shift and change the engine rpm to match the next gear you may only vary the crank rpm by 700rpm but the supercharger is spinning in excess of 13000rpm or more depending on setup and brand and any little change in crank rpm will drastically affect the superchargers rpm. You need this slipage to let the rpms match and let the boost settle down between shifts.

There is ALOT of engineering that goes into this and is for extending the life of the system.

I might be talking out my a$$ since most of the stuff i know is for roots-type blowers but i think most of the same stuff applies. Its also harder to explain since you can have a BOV on a centrifigul blower.

 

The bypass valve on the Vortech and Procharger opens when you shift gears....

When I'm driving my car hard (very rarely) and drop down too many gears at once I can feel my serpintine belt slip and I can tell you that NO system should feel the way it does. I am just too lazy and don't care enough to change the belt (since I'm taking it off soon).

It seems like a lot of the roots type blowers I've seen have HUGE cog belts. How can they slip? If they did slip they would destroy the belt. I have no experiance with roots type blowers so I guess I really have no idea....

 

What you are feeling is normal. Roots with cog belts are for racing only or should be, you will not find any roots blower with a cog belts from the factory (ie, jaguar, ford lightning/cobra/gt, some others that im not thinking of right now).

 

I'm thinking of older muscle cars that have big blowers on them. You always see huge cog belts on them. Factory roots blowers (to my knowledge) never run at high boost, so a big belt wouldn't be as necesarry.

When I first got my supercharger the serpintine belt never slipped, but as I ran it harder and harder and started getting some oil on the belt it started to slip. With the way our superchargers are geared I can't see an advantage to slipping at any time.

I'm by no means an FI expert but I do have a little experiance here and there with super chargers. Everything I've seen, read, and heard has said that proper belt tensioning was essential to prevent belts from slipping which in turn would reduce output....

 

No, I called them to buy a cog upgrade pulley and belt and THAT's when they told me the slippage response.

 

oh so you never put cogged pullies on? How did you get rid of your slipping?

 

I upgraded to a thicker GATES belt.