I'll give you guys the tech on BOVs. First off I bet the race team doesn't use the BOV because it doesn't work well. I've probably tuned with every BOV made and you would think its impossible for them to leak but some do and the best do not.
A BOV actually works off of pressure differential between the top chamber and the bottom of the valve (part connected to the charge pipe). This is why a BOV can vent at partial throttle and it's part of the reason why a drifter or racer my not like how the BOVs reacts to throttle inputs. If you bov has a light spring pressure differential is reached easily causing the bov to dump and therefore the driver must continue to dip into the throttle more and more to maintain speed. I can't stand that so I run a BOV that not only has a very stiff spring (requires high pressure differential) but also bas preload adjustmentt to fine tune it. This way when I apply 50% throttle boost increases and I get a steady rate of acceleration and my BOV only dumps when I slam the throttle shut.
Ok nerd button off
Thanks,
Phil Grabow