Home › Forums › Stay Dirty Lounge › Service and Repair Questions Answered Here › Covering exhaust flex pipe with aluminium foil tray.. safe? › Reply To: Covering exhaust flex pipe with aluminium foil tray.. safe? June 14, 2020 at 8:41 pm #957476 NathanParticipant This isn’t a scientific answer or even an anecdotal one, but I’d think if it was wrapped tight enough that it won’t rattle it might be too tight to breathe effectively.