STI — Stage 2 ECU Tune
- 21% power increase
- 8% torque increase
- Improved fuel efficiency
- Enhanced boost control
- Optimized fuel injection mapping
- Refined power delivery and reliability balance
This 2017 STI runs the usual Stage 2 hardware that suits the factory block: aftermarket intake and exhaust, a top-mount intercooler, high-pressure fuel pump, and a blow-off valve. The calibration targets 1.2 bar boost on 98 RON, lifting output from 149 kW to 180 kW at the wheels with 267 Nm torque—a 31 kW gain that sits well within sensible limits for the EJ25 on pump fuel.
The factory ECU responds well to these changes once fuelling and load tables are properly addressed. Timing has been adjusted to suit the octane ceiling and boost level, keeping detonation margin safe for track and spirited off-road use.
The dyno result reflects a typical reliable outcome for this combination. It's not chasing maximum numbers, just extracting what's there with the hardware fitted and keeping the engine in one piece.
Is this safe for daily use or just competition?
The tune is framed for off-road and closed-circuit competition use. The hardware and 1.2 bar boost level are conservative for the EJ25, but reliability always depends on maintenance and how it's driven.
Can I run this tune on 95 RON?
No. The calibration is built for 98 RON. Running lower octane risks detonation and engine damage.
What's the limiting factor at Stage 2?
The factory block and internals. Beyond this, you're looking at supporting fuel delivery upgrades or a built bottom end if you want more boost or power safely.
Workshop & Dealer Access
Protunes supplies ECU calibration files exclusively to approved workshops, tuners, and dealers throughout Australia. Platform: Factory.
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