On our project car, Gump, we’ve implemented this hybrid strategy using a Turbosmart StraightGate for cold-side control and Turbosmart traditional wastegates on the hot side. This setup delivers smooth boost ramps, optimized backpressure, and free horsepower at higher RPM.

To enhance control, we utilized CO2 to manage both hot-side and cold-side wastegates. By using two 3-port solenoids, we could switch and blend control methods dynamically. These solenoids gradually cut the reference boost, and when fully cut, they would close the gates, offering precision in managing boost pressure.

The hardware behind that is our high flow dual solenoid boost controller (U019), a billet manifold with both solenoids preinstalled, fed by a CO2 bottle and regulator kit in single or dual wastegate form. Turbosmart hardware is in wastegates, and if you are fabricating the hot side, our 316 stainless wastegate merges fit 2.5 inch tubing with 45, 46 and 50mm flanges.

Hot-Side Control: Turbosmart’s traditional wastegates regulate exhaust flow to maintain turbo speed and prevent boost overshoot. They stabilize turbo performance, especially at peak boost.

Cold-Side Control: Using the Turbosmart StraightGate, cold-side systems precisely manage intake-side airflow, allowing better tuning during launch and transitions. It ensures consistent pressure and a refined boost ramp.

• Boost Ramp Control at Launch: The Turbosmart StraightGate ensures smooth and predictable boost delivery during the two-step or launch, maximizing traction and minimizing turbo lag.
• Backpressure Optimization Down the Track: Traditional Turbosmart hot-side wastegates dynamically manage exhaust flow to maintain optimal backpressure ratios, improving turbo efficiency and unlocking additional horsepower at high RPM.
• Dynamic Precision with CO2 and Solenoids: By blending both control methods using CO2 and solenoids, we achieved fine-tuned adjustments. Gradual cuts in reference boost allowed seamless transitions between hot-side and cold-side control, ensuring precise performance throughout every phase of the track.

On Gump, this hybrid strategy has allowed us to:

• Precisely control boost ramps during launch for consistent traction.
• Eliminate unnecessary restrictions at high RPM, unlocking free horsepower.
• Maintain optimal backpressure ratios for improved turbo efficiency.
• Seamlessly switch between control methods for maximum flexibility and efficiency.

One thing to sort out before you trust any of this: the dome sensor. At this boost level the pressure spikes that reach a sensor are what kill it, and a dome sensor that fails high tells the ECU to vent and cut CO2 — we have the datalog of exactly that happening, in sensor protection 101. The BPS boost control kit bundles the controller, the surge dampener and the CO2 setup together for that reason.