Engine twin scroll turbochargers?

twin scroll turbochargers?

i'm slowly learning about turbochargers and I came across something called twin scroll. The descriptions i found off google arent exactly clear. Could someone explain it?

that sounds like sequential turbochargers.... basically, big turbochargers give you great power at the lost of lag. Small turbochargers gives immediate boost but lack power. Link the two together.. small and big turbocharger run at the same time.. small one will out power the big one in the beginning... so you take off without lag.. but at higher speeds the big turbo takes over giving you that big turbo power.

www.howstuffworks.org ..or net.. or com... i don't quite remember.

uh....yeah. its one turbocharger, not two put together.

are you sure its not a supercharger? They make a <i>twin-screw</i> design... is that what you mean? I've never heard of a twin scroll turbo.

Evo´s bring twin scroll turbo chargers... its basically what sins says but all in 1 turbo

From mitsubishis website: (Lancer Evolution Description)
"The secret to getting 271 horsepower from a 2.0-liter 4-cylinder engine is air flow: The Lancer Evolution VIII's twin-scroll turbocharger delivers high boost from low engine speeds by minimizing exhaust obstruction. Dual exhaust passages from the engine to the turbine housing guide the exhaust gas smoothly to the turbine to improve low and mid-range torque and engine response."

i've never heard of a twin-scroll turbo charger. keep in mind, car advertisers are advertizing to the general public who most don't know a ton about cars. they guy who i went on a testdrive with my corolla said that if i supercharged it, its a 12 second car. i laughed at him.

Yes u can say that. It's kinda like how proper headers are designed. Each pulse from each exhaust port is staggered so that they don't collide with eachother in the collector. Also by doing this the vacuum it leaves behind helps to pull the next exhaust pulse along.

I've definitely heard of twin-scroll turbos, but not exactly sure what they are. Sounds like Sins is right though.

The Subie guys seem to know a little more on the subject.

http://forums.nasioc.com/forums/sho...ght=twin+scroll

twin-scroll turbos are also called divided inlet turbos. All it really does is it keeps the exhaust ports seperated from eachother until it hits the turbine of the turbo. By doing this the exhaust gas pulses remain strong all the way to the turbo which help spin the turbine quicker (than single inlet turbos) at low rpms. The turbine itself is exactly the same as single inlets. Its really the turbo housing the manifold that is different.

So, instead of the exhaust pulses hitting the turbine together, they hit it separately, causing the turbine to spin faster and thus create more boost at lower RPMs....