How to Build Performance in Four Cylinder Enginesby Shayrgo Barazi
Building a performance four cylinder engine is much more difficult than building a six or eight cylinder engine because of displacement. Bigger engines simply transfer more air through the motor which results in high net horsepower and torque, thus the saying, "No replacement for displacement." However, it is still possible to obtain decent results with a four cylinder motor with many techniques utilized in the motorsports industry.
Install headers and a full catback exhaust system to allow the engine to breathe more freely. The stock exhaust is very restrictive on four cylinder engines, and a lot of horsepower can easily get freed up by simply installing a larger diameter exhaust system.
Replace the intake tube and filter with a cold air intake. The stock air intake system is very restrictive; it is designed this way to limit the amount of noise you hear under the hood. A cold air intake will re-route the intake hose to the front bumper where colder, denser air will be directed towards the motor. Denser air ultimately means more air in the engine and more power.
Install aftermarket camshafts in the motor. The stock intake and exhaust camshafts are designed for a high miles per gallon figure and not for performance, which limits power and torque. Aftermarket camshafts allow the valves to remain open for a longer period of time, allowing more air to enter the engine to increase power.
Install high compression pistons in the motor if you plan on keeping a naturally aspirated motor. High compression pistons allow more ambient air to enter the motor by repositioning the engine geometry with new pistons. For the engine to handle this increased load, high performance rods must be installed with the high compression pistons. However, turbocharging or supercharging is a much easier method of increasing the power of your four cylinder. If you would rather take this route, then install low compression pistons in your motor as high compression pistons will cause spark knock, detonation and extreme engine damage.
Install a turbocharger or supercharger on your motor. The turbocharger and supercharger are classified under the realm of forced induction and are by far the easiest, quickest and cheapest method of increasing horsepower and torque out of a four cylinder engine.
Install an engine tuner to add more fuel to compensate for the added air that is entering the motor. A balance between air and fuel must be maintained so that the engine runs smoothly and efficiently. An engine tuner will plug into your OBD II (On Board Diagnostics) port and will automatically increase the fuel injector pulse width to compensate for the increase in ambient air in the engine.
- After installing all of your aftermarket parts, take your vehicle to a tuning facility that has a dynamometer so that they can fine tune your engine for maximum performance.
- Always place jack stands beneath the vehicle before doing any work below it and wear safety glasses.
Items you will need
- Ratchet and socket set
- Jack stands
- Cold air intake
- Aftermarket camshafts
- High compression pistons and rods
- Engine tuner
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