In addition to high-temperature capability, the Honeywell VNT™ racing turbo for Audi R15 also delivers precise control through Rotary Electric Actuator (REA) and provides superior transient response by featuring its world-leading ball bearing technology.
The turbocharger's basic design was conceived for we with the 5.5 litre twin-turbo engine complying with the LMP1 category regulations (ACO) valid for Le Mans. The design was tailored for the mass flow limited by the restrictor upstream of the compressor. Another design criterion exists in the boost pressure limitation stipulated by the regulations.
With conventional wastegated turbochargers or fixed geometry turbochargers (FGT), a turbine flow area cannot be adjusted during operation.
Knocking is abnormal combustion in which the air-fuel mixture ignites prematurely due to exposure to high temperature and pressure, creating an unwanted high-frequency noise. When the compression ratio is increased, the temperature at compression top dead center (TDC) also rises, increasing the probability of knocking.