Choosing a turbocharger: five common mistakes
The mistakes that make an expensive turbo drive worse than the stock one. All five turn up regularly.
1. Choosing by peak power
A turbo sized for 800 hp on an engine that will make 550 is lazy down low and only wakes up past 5000 rpm. On the road that is worse than stock.
2. Ignoring the fuel system
More air demands proportionally more fuel. Stock injectors and pumps have a ceiling, and it arrives before the turbocharger's does.
3. Building around 100 octane
If that fuel is not available where you drive every day, a map built for it is useless. Calibrate for the fuel that actually goes in the tank.
4. Forgetting the transmission
Torque kills gearboxes long before power kills engines. On most builds the transmission is the second-largest cost, and it has to be planned from the start.
5. No monitoring
Without exhaust temperature and fuel pressure readings, any high-output engine is a lottery. Gauges are cheaper than a rebuild.