Description

The SV50 uses a v-band mounting system that is compatible with existing common v-band flanges. The billet hinged clamp design is both easier to use and stronger than other flexible band-clamp designs on the market. Why do we use a one-piece brass piston instead of a diaphragm like other brands? For good reason – good quality diaphragms are typically constructed from silicone and reinforced with a nomex cloth, and are usually a“rolling” design that allows relatively long piston strokes. However, this design has its limitations. The most significant being they are only designed to have pressure applied to one side, which is the underside. The nomex reinforcing is on the top of the diaphragm, so that the silicone is blown INTO the cloth. Applying pressure to the cloth side can result in the silicone material de-laminating from the cloth. Secondly, applying pressure to the wrong side of a rolling diaphragm causes the bellow section to collapse on itself. This creases the nomex reinforcing, and also causes friction and wear as the piston starts to move when the pressure changes to vacuum.

BOVs must deal with both pressure and vacuum. Combine this with the fact that competitors’ products use wastegate diaphragms constructed the wrong way around for use in a BOV, and it’s clear a diaphragm is not the ideal solution. By using a robust and proven piston design, and carefully machined to close tolerances, the SV50 eliminates the diaphragm and the problems associated with them when used in a BOV. This is how the SV50 can be made to withstand such high boost pressures.

The SV50 comes with two springs and an adjustment screw, with which you can set the SV50 up for idle vacuum ranges from 5-22”Hg (2.5-11psi vacuum). This range covers anything from superchargers or all-out race cars, all the way to street driven cars with stock cams and high idle vacuum. Other brands rely on swapping springs to set the valve up to the engine’s idle vacuum. Springs that you have to pay extra for. The SV50’s v-band clamp is machined from billet, but that’s not the unique feature. Competitors’ one-piece designs rely on bending the clamp material to open up the clamp, with difficulty. Repeated bending will also cause the material to fracture. GFB’s 2-piece hinged design solves this problem by opening wide for easy installation and lasting longer than other designs.