no dump valve mate chatter is the way forward! when i had my first engine built by area six it was running t34 with 31 actuator and sounded fookin wicked and was running a genuine 280/300bhp @ 20psi . i brought a brand new forge motorsport dump valve and ian chucked it in the bin , i said what you fookin doin and he handed me the car keys and said check that noise out , that was it never looked back and never caused any trouble . only if your running high bhp and then its a race port
in derby we got a carpark thats like a tunnel and when we used to drive through that at night it used to have people on there hands and knees
good i miss my car