Are there any articles about a hot exhaust expelling gases faster? Just quite interested as i am technical guy and we're here to gain knowledge.
I actually don't see how it would expel the gases faster. The gases are pushed out by the exhaust pressure of the actual engine. The only real advantage i see here is the fact that it will lower the engine bay temperatures which is handy if you have a top mounted intercooler.
I found this on an American toyota site,
David Fain's cheap exhaust trick
"One cheap way to get extra power and fuel economy is to wrap your exhaust manifold/header with heat resistant exhaust wrap/tape.
"When exhaust gases are pushed out of your cylinders to your exhaust manifold, the air surrounding the manifold begin to cool the gases. This cooling process reduces the velocity of the escaping gases and the engine must 'work' to push the gases through your exhaust system.
"Wrapping the exhaust headers with exhaust wrap maintains hotter exhaust gases that exit the system faster through decreased density. Increased exhaust scavenging is produced, along with lower underhood and intake temperatures. I would also venture to guess that my catalytic converter operates more efficiently since hotter gases would elevate burning of pollutants.
"I purchased the exhaust wrap by a company called Thermo Tec from a JC Whitney catalog for around $30. I installed the wrap on the header and a portion of the exhaust pipe leading from the catalytic converter to the muffler.
"This mild enhancement resulted in a 5 - 7 HP gain ... the power surge starts at around 3,000 rpm. I haven't had the chance to monitor the fuel economy gains."