vortech??

V1 and V2 are not self contained, they both get fed by the motor and returned to the pan.

The V2 is the SQ series which has a helical gear to make them quieter, all the V1 are straight gears, older technology and loud as hell...lol

The S is the largest street series blower they make, after that you can go T-trim which is the largest blower that will fit in that series bracket, while streetable not reallt ideal. They they have the YS, YSi, X and XX blowers...older units were A trim (smallest entry level blower replaced by the new SC, B-trim and R-Trim both phased out and replaced by S-trim) The differnce in the trims is the impeller size, the speed it needs to be efficent, the max speed of the impeller and max HP potential. They also have many otehr trims for smaller cars, G-trim, F-trim, E trim etc... http://www.vortechsuperchargers.com/scspecsheet.php

The amount of boost depends on your engine and what blower and crank pulley it comes with.

And please note the v2 is still noticable. People know i have a blower, its just not rediculously loud like the v1 or a prochrager!! but different strokes for different folks

Its not the rib of the pulley, its the diameter that increase boost...small blower pulley more boost, larger crank pulley more boost. You can play with the ratios to optimize your set-up, just don't exceed the maximum inpeller speed.