Other versions of the VTA are designed for use on cars that do not have any kind of factory-fitted diverter valve. Vehicle manufacturers have deleted the troublesome solenoid type diverter valve from some of the newer models, but this leads to turbo compressor surge which can be taxing on the turbo in the long run. The VTA valves for these cars are designed to re-introduce the function of a diverter/blow-off valve to help protect the turbo in the long term and also provide a blow-off sound.