Silvia S14 — Stage 3 ECU Tune
- 4% increase in peak power output
- 22% increase in torque delivery
- Dual boost configuration capability 1.4 & 1.7 bar
- Early boost onset at 2500 RPM
- Improved throttle response and acceleration
- Enhanced fuel system management on E85
This is a proper off-road/circuit S14 build running E85 through an Apexi Power FC. The SR20 is fitted with Tomei poncams, a Garrett mid-frame turbo, upgraded injectors, high-pressure fuel pump, and electronic boost control. The calibration was developed around 1.7 bar of boost, balancing the aggressive cam profile with the turbo's efficiency range on ethanol.
The dyno sheet came back showing 258 kW at the wheels with 392 Nm of torque. The torque lift is notable — a 72 Nm gain over the baseline 320 Nm — thanks to the E85 cooling and the turbo's response characteristics. The Power FC gives good control over timing and fuel on this platform, and the tune takes advantage of ethanol's octane tolerance without pushing the motor past sensible margins for a weekend competition car.
Why only 10 kW gain if it's a full Stage 3 build?
The baseline was already at 248 kW, so this was a turbo and fuelling refresh rather than a stock starting point. The real story is the 72 Nm torque gain and improved delivery on E85.
Is the Power FC adequate for this spec on E85?
Yes. The Power FC handles E85 fuelling and timing well with proper setup. It's a proven platform for SR20 builds at this power level, especially with external boost control.
What's the benefit of running 1.7 bar on E85 over 98 RON?
E85's cooling effect and octane rating allow higher boost and more timing without detonation risk. You get more torque and power safely, though fuel consumption increases and availability needs consideration for competition use.
Workshop & Dealer Access
Protunes supplies ECU calibration files exclusively to approved workshops, tuners, and dealers throughout Australia. Platform: Apexi Power FC.
Apply for Workshop Access