This B48/B58 platform Performance Heat Exchanger Upgrade (air-to-water intercooler upgrade). This performance upgrade dramatically improves turbo/inlet air cooling by providing double the cooling surface area and over three times the fluid volume compared to the factory cooler. The benefits are more noticable during back to back runs at higher boost levels where the factory cooling capacity can be overwhelmed. This leads to an ignition timing pull and reduced turbo efficiency. Direct bolt-in installation.