Audi takes the technological revolution to a whole new level. The famous car manufacturer presents its latest achievement under the bonnet – an electric supercharger. In this way the hated by any driver turbo lag is totally eliminated. What actually means the turbo lag? Turbo lag is the low RPM range, in which the exhaust gases are not enough compressed to push up the turbo. Then it not able to spool up a boost to the engine. This often happens in lower RPM range , or during driving as a delayed throttle response.This has been the subject of engineer’s efforts for three decades.
Audi’s new system, however, totally eliminates lag, greatly improves low-speed performance and is fundamentally simpler than the twin-turbo and triple turbo set-ups.
What Audi adds to their V8 engine is:
On the basis of those simple elements is built the super-revolutionary technology of Audi’s electric supercharger. The idea is to use a electric compressor to pull an additional air quickly enough to compensate the turbo lag.
The air inflow traditionally starts through one or both of the turbochargers, then it goes to the two intercoolers, and from there it combines. Once combined, it is after that split between the two manifolds leading to the cylinder packs. What Audi’s supercharger does is to flow in air fast over-leaping turbocharger and intercoolers. In that way the air inflow goes faster to the manifolds and cylinders and the acceleration starts immediately with no turbo lag produced. After the initial start, later supercharger is not needed and the engine operates either like single-turbocharged or like twin-turbo. All the air used by those system is led out through a single exhaust pipe.
What Audi’s supercharger does is shortening the response time between the initial press on the gas and the moment the turbo kicks in - just a third of a second. For this time the compressor spools up to 70 000 RPM and provides immediate boost, thus avoiding the turbo lag. In this case, the valve from the intercooler will be closed and the compressor directly pulls the air into eight cylinders.
After you once start accelerating, in low to mid RPM's range, the car will rely to only one turbocharger. At that moment, the electric supercharger is off.When the RPM's range grows from mid to high values, the second turbocharger kicks in and joins the first one. Then the car works as twin-turbo one.
A brave and clever decision is the way the cylinder exhaust valves work. Each cylinder has one exhaust valve for each of the turbochargers. When the RPM's range is low-mid, work only the valves for the first turbocharger. As the RPM-s grows to mid-high, the second valves on each cylinder start to contribute the second turbocharger.
In this way, Audi’s vehicles
