The APR R1 diverter valve is meticulously engineered to endure high pressures without failure. It seamlessly integrates with 1.8T 20V engines in models like the Golf 4 GTI, Leon 1M Cupra, S3 8L, and TT MK1, as well as 2.7T engines in the Audi S4 B5 and RS4 B5. This valve, with a recirculating design..