The turbo was developed to cut the put of belt-driven superchargers as they were comp horsepower. The speed of the exhaust Gauze drives the turbo. A turbo is two turbine wheels on a commonplace shaft in a housing, comparable in appearance to a snail shell. The two turbine wheels are segregated by a wall in the housing, forming two seperate intakes and exhausts.
The turbo takes in air and forces it (under compression) into the intake manifold, effectively increasing the engine displacement. Increasing the engine displacement also increases horsepower considerably. The turbo is situated near or on the exhaust manifold and has exhaust directed through one turbine. That turbine turns the other turbine at equal speed, compressing the incoming air.
The compressed air is then directed through an intercooler. An intercooler resembles a normal radiator. The turbo has a line from the oil filter housing to the turbo center bearings and then back to the oil pan. Turbos can't be used on high-compression engines. The overall compression can't be over 9.5 to 1. To prevent excessively high pressures that could compromise the cylinder head gaskets or pistons, a blow-off valve is installed. Its job is to simply allow any excess pressure to escape without harm to the engine.
The upside of turbos is that they are free horsepower and don't hurt fuel mileage. This is the only upside, because they're the same in terms of cost and maintenance. Turbos require more plumbing and produce a lot of heat under the hood. From a horsepower standpoint, they can produce as much horsepower as a supercharger. However, like superchargers, they have an inherent lag.
A turbo doesn't become effective until an average of 3,000 rpm is achieved. This makes it a part-time power increase. It uses the stock oil system of the host vehicle by tapping into the oil pump pressure near the oil filter. This cools the air and makes it denser. Without the intercooler, hot air would be forced into the manifold, causing preignition or detonation. The turbo's speed will increase or decrease with engine speed, thus increasing compression.
