supercharging and turbocharging?

[john_trickle]

What are the differences really between supercharging and turbo charging?

Supercharging and Turbocharging are alike in the fact that both are pressurizing the combustion chamber with the air and fuel mixture rather than relying on a suction effect. Turbochargers use the exhaust gas to spin a turbine wheel that is connected by shaft to a compressor wheel. For this reason, there are two sides/housings to a turbo, a hot and a cold side or the turbine and compressor. A benefit to this design is no parasitic losses, the exhaust gas provides the rpm for the wheels. The shaft and blades reaches speeds of 120,000 RPM. A Supercharger uses a belt drive system to drive the cold side of the unit. There is no hot side because of this, just one blade for compressing air. The upside to this is a bit lower component temperature and an absolute linear power curve. In typical motorcycle applications most find them to give a bit too much power on the bottom end because of that curve. The downside to Supercharging is the lack of flexability when it comes to boost pressure control. More or less if you want different power you have to change pulley diameters. Some individuals have found supercharging to be the way to go when using motorcycle engines in other vehicles such as Lotus 7s and other such vehicles.


john