With an external wastegate setup, the wastegate flow can be reintroduced to the exhaust flow coming out of the turbine wheel at a nice and gentle angle such as on this Armageddon twin-turbo kit for the Camaro. This reduces disturbance to the main exhaust flow and reduces the back pressure on the turbine wheel.
If you’re building an all-out track car for maximum power and money is no object, the answer is easy, go with an external wastegate and dump the flow. In the real world where noise, emissions, costs, packaging space, and simplicity are concerns, the internal wastegate will obviously still do the job. There will just be power left on the table.
Read our past turbo tech features below!
Turbo Tech: Size Matters!
Turbo Tech: Size Matters! – Part 2
Turbo Tech: Generating Compressor and Turbine Maps
Turbo Tech: Compressor and Turbine Map Details
Turbo Tech: Turbo Bearings
Turbo Tech: Troubleshooting
An Inside Look at the New Garrett GTX Turbochargers
BorgWarner EFR Turbo Feature Set