Now, I know that anytime you mention “electric” and “turbos,” visions of eBay scam listings probably fill your head. But, let’s put that all aside for a few minutes, and talk about actual hard electronic component integration into turbocharging. Sure you’ve heard of electronic boost controllers before, but this is something totally different — enter Turbosmart‘s electronic wastegate.
Basics of Boost Control
As a quick refresher, let’s look at how boost control works for a turbocharged combination. The wastegate is a poppet valve plumbed between the exhaust ports of the cylinder head and the turbo’s exhaust wheel. In its most basic configuration, the wastegate is controlled by a spring that resists manifold pressure, directly. A 7 psi spring would hold the valve closed up to 7 psi of manifold pressure, before allowing the valve to open and bleed off exhaust gasses to control the speed of the compressor wheel.
The most basic form of boost control is a simple screw valve that simply creates a controlled leak between the manifold pressure source and the wastegate, allowing the boost to rise to levels higher than the mechanical rate of the spring installed in the wastegate. Modern electronic boost control is still largely reliant on boost pressure and mechanical springs for the actual mechanical operation and is simply electronic interruption of the reference boost pressure to the mechanical wastegate.
Real Electronic Boost Control
Long known for its line of high-performance external wastegates, Turbosmart took the next logical step in electronic boost control by putting an electronic actuator directly on the wastegate itself. By integrating the electro-mechanical control directly into the wastegate, a level of control is achieved that was previously only available through a complicated system of solenoids and auxiliary pressurized gasses.
The new electronic wastegate design uses no springs, instead controlling the exhaust valve entirely through mechanical means. That not only offers precise actuation options, but also inherent resistance to exhaust pressures, meaning no boost creep or leaks from worn-out wastegate springs or a leaky CO2 connection.
One concern that has long been voiced is the speed at which electronic control could react to demanded changes. Turbosmart’s electronic wastegate opens at a rate of 72mm of valve travel per second allowing for full travel of the valve from fully closed to fully open in a scant 290 milliseconds. That speed is achieved without a tradeoff in accuracy, with the onboard high-resolution valve position sensor, making for a simple six-wire installation (power, ground, and then the position sensor and internal temperature sensor wiring).
Compatible with any programmable ECU which has an available analog input and high current output, the wastegate is controlled like a drive-by-wire throttle body in the ECU’s software. Built on Turbosmart’s GenV wastegates, the electronic wastegates are available in four sizes, ranging from 40mm on the small end up to 60mm on the large end, to cover a range of power needs and to fit existing wastegate flanges.
While electric turbos might still be a ways off, Turbosmart’s electronic wastegates are a reality and offer a level of control over boost pressures that were only dreamt of even just 10 years ago.