The Aeroflow Performance universal compact vent to atmosphere blow off valve is designed to keep your turbo shaft speed at a maximum whichis greatly reduced in speed bychanging gears or backing off the throttle and the air foundin your intercooler pipes bouncing back off the throttleblade and surging against the compressor wheel causing it toslow and feel lagging when thenext gear is pulled. For use on turbocharged and supercharged applications. Thebody components are CNC-machined from 6061 aluminium alloy with brass internals. The adjustable top body can be screwed in each direction to provide increasedor decreased spring tension with added shims to internallyadjust this for more spring tension. An alloy and stainless weld on pipe are included in each kit. These weld on pipes lock onto the bottom of BOV via a lock ring with grub screws to secure into place and seals with a Viton O-ring. The outlet screwin barb included in the kit is32mm barb. Various other sizesare sold separately under our plumb back barb adapter range (20mm up to 38mm).