I have a weird noise coming from the engine. I have a custom airbox and vented BOV but when I give it full throttle it makes a kind grinding noise if u could call it grinding but its definalty only just started to happen, I really cant explain the noise but yeah it wasnt there the other day, or I might not of noticed. Its not making any differnece the performance if anything it has increased the power also I havea like whistle sound as im driving round off boost I have checked all piping and its ok so im kinda stressed as to why it has just started to happen CAn someone shed some light on this situation thanks