Exhaust gas gas is undesirable, noxious, or toxic substances, such as carbon monoxide (CO) from incomplete combustion, hydrocarbons (properly indicated as CH, but typically shown simply as "HC" on emissions-test slips) from unburnt fuel, nitrogen oxides (NO) from excessive combustion temperatures, and particulate matter (mostly soot). Exhaust gas temperature (EGT) is important to the functioning of the catalytic converter of an internal combustion engine. It may be measured by an exhaust gas temperature gauge. EGT is also a measure of engine health in gas-turbine engines (see below). During the first two minutes after starting the engine of a car that has not
Exhaust heat management performance and avoid burns from motorcycle exhausts. Heat wrap consists of a high-temperature synthetic fabric which is wrapped around the manifold. Often sold as a cheap and easy way to boost horsepower, exhaust wrap does not increase engine output much. It can decrease engine bay temperatures and increase exhaust velocity. Lower intake air temperature — and therefore increased air density — may result in an increase in engine efficiency and power. Hotter exhaust gases travel faster which may reduce turbo lag and improve exhaust gas scavenging. There has been much debate if heat wrap is better than plasma-sprayed coatings. The