I've noticed a bit of a tappy noise from my fury... Bonnet open - can't hear it. Sweet as a nut, no vibration.. Nothing.

When I close the bonnet and drive it there it is. It's not alarming or anything but I wa just wondering why it appears when the bonnet is shut. It's proportional to revs so it's nothing daft like the front clam making noise. It's not tappy valves because I can't for the life of me hear it at any revs with the bonnet open and my ear next to the engine. Only thing I can think of is the exhaust headers/silencer blowing a bit. The silencer hasn't been repacked for a good 3k miles and it sounds like it's coming from that area, kinda sounds like it's coming from the passenger footwell/under dash. I don't think it's anything to worry about by any means. It's running better thN ever. I'd just like to know what it is..

So could a blowy BEC exhaust make that kinda noise??