Initial testing revealed a fluttering sound coming from the Turbonetics blow-off valve, which was obviously inadequately small (rated at 500bhp) and leaking boost no matter how tight we set the spring. We tried Turbonetics' Godzilla unit with a 38mm flange opening that's 27 percent larger in diameter. Figuring out Pr2 gives us an exact 60 percent improvement in flow, or 800 bhp, which Turbonetics also rates it at. The Godzilla blow-off valve vents at the front before the intercooler. We were pleased to see our AEM logs revealed a 300 to 400 rpm improvement in boost response during road testing. Thanks go to Imagine Auto for welding the Godzilla flange for us.