What are the effects of using leaded or unleaded petrol?

Answer 1

The answer is very obvious. Before 1975 cars used leaded fuel which burned at lower temperature and didn't have cat converters in the exhaust. This also formed a lubricating layer within the cylinders as lead turns to liquid at low heat temps, but as everyone knows, lead is bad for the environment and is very toxic to anything living, and even today the highest levels of lead in the ground (and this is true all over the world) is along sides of roads and highways that were around before 1975 as the leaded gas fumes settled along the roadsides, and that's thousands and thousands of miles worth. After 1975 cars burned unleaded gas which meant that the engines all had to be redesigned with different metals as unleaded gas burns much hotter (old cars use to run at about 160 degrees to 180, but new cars run at 200 to 210), and if you used unleaded gas in a car the needed leaded, it would burn much hotter and fry the engine,. The same is true in reverse. Put leaded in a car the requires unleaded and you now have an engine that's loaded up with carbon, and a clogged cat converter that will not allow your engine to run more and more as it builds up in the cat until it will not even start because it can't eject any exhaust. It's like stuffing potato's in your exhaust and then trying to start your car. The result of all the gas fumes building up in the exhaust will result in a big BOOM as the gas ignites within the exhaust system. The cat converter is designed to get very hot, and burn off any unburned fuel that made it past the cylinders (Hydrocarbon) as to help with environmental issues.