These 10 Performance Upgrades Make the 2025 Honda Civic Si a Solid Sports Sedan

These 10 Performance Upgrades Make the 2025 Honda Civic Si a Solid Sports Sedan originally appeared on Autoblog.

Make the sporty Civic even better

The 2025 Honda Civic Si takes the humble compact sedan and gives it a sporty edge. It may not pack neck-breaking power, but with 200 horsepower and 192 lb-ft of torque churning from its turbocharged 1.5-liter engine, it is quick enough to keep things fun. In fact, some tests show that it can sprint to 60 mph in around 6.6 seconds. But where the Civic Si really shines is in the corners.

2025 Honda Civic SiHonda

The car’s steering is super responsive, especially when it’s put in Sport mode, and its firm suspension gives it an edge in the handling department. Unlike its Acura Integra cousin, the Civic Si doesn’t have adaptive dampers, but its fixed suspension is well-balanced for everyday commuting and holds up well under slow- and high-speed cornering. However, although the 2025 Civic Si is quite the pocket rocket and really doesn’t need anything to be an enjoyable car to drive, it can always be better.

For all its strengths, the Civic Si has room to grow. Thanks to plenty of aftermarket support, enthusiasts can dial up the car’s power and handling prowess with the right upgrades. If you’re looking to take your 2025 Honda Civic Si to the next level, these 10 performance modifications will transform it into a “Civic Type R lite.”

#1. ECU tune or reflash

One of the easiest ways to unlock the full potential of the Civic Si’s turbocharged 1.5-liter engine is with a performance tune that improves the car’s throttle response, increases boost, and adds anywhere from 25 to 40-plus wheel horsepower. Three of the most popular ECU tuners include Hondata, KTuner, and COBB tuning.

#2. Cold air intake system

Since the Honda Civic Si is turbocharged, it can benefit from increased airflow. One way to accomplish this is to install a high-flow intake to help the turbo breathe better. What results is more power and some aggressive intake sounds for more driving excitement. Some popular brands include K&N, Injen, and Takeda, all of which have different types of intake systems and various pricing for them.

2025 Honda Civic SiHonda

#3. Upgraded intercooler

The Civic Si comes with an intercooler, but a more efficient intercooler can reduce heat soak and maintain consistent performance under hard driving or track use. According to PRL, a company that produces these upgraded intercoolers, you can expect about a five to 10-horsepower increase over stock.

#4. High-flow exhaust system

A high-flow exhaust system can uncork the engine by reducing backpressure, allowing the Civic Si to sing with a louder exhaust note. Some exhaust manufacturers claim their systems can add around 10 more horsepower to the Civic’s base output.

2025 Honda Civic SiHonda

#5. Lowering springs or coilovers

Although the Civic Si handles well in its stock form, its suspension can be upgraded with a set of lowering springs or coilovers. Lowering springs will lower the center of gravity to sharpen its handling and improve the car’s stance, while coilovers allow full adjustability for street or track tuning.

#6. Lightweight wheels and summer tires

Shedding unsprung weight by adding a set of lightweight wheels can improve the Civic Si’s handling and performance, while a set of stickier summer tires can improve its grip. Better grip can give the driver more confidence under hard cornering.

2025 Honda Civic SiHonda

#7. Upgraded pads and rotors

A set of upgraded brake pads and rotors can give the Civic Si better stopping power. By replacing the stock brake pads with fade-resistant units and the rotors with slotted or drilled ones, the Civic Si will feel more confident when braking before the turns when driving at high speeds. And while some enthusiasts will opt for a big brake kit, that’s not completely necessary if you’re mainly driving the Civic on the streets with a few track days here and there.

#8. Short-throw shifter

The 2025 Civic Si has a very smooth shifter from the factory with very good engagement. However, if you’re the type of driver who likes the feel of a sports car shifter with a “click-type” action when going gear to gear, buying a short shifter kit could give the car the shifter feel that you’re looking for.

2025 Honda Civic SiHonda

#9. Performance clutch kit

With more power comes a greater chance of other parts, like the clutch, slipping. Adding power can overwhelm the stock clutch unit, so it’s recommended to get a stronger clutch kit to hold the additional power and give the car a sportier feel at the same time.

#10. Strut tower brace and chassis reinforcement

Like adding lowering springs or coilovers, adding a strut tower brace and other chassis reinforcements can greatly improve the Civic Si’s handling characteristics. Extra bracing can give the car sharper turn-in and reduced body flex during hard cornering, giving the Civic Si a more planted and responsive feel.

2025 Honda Civic SiHonda

Final thoughts

Although the 2025 Honda Civic Si is an excellent platform straight out of the factory, it can always be improved upon. A larger intake and exhaust system, ECU tuning, and some suspension work can easily allow it to keep up with the Civic Type R and other rivals on the road. If you’re an enthusiast who is looking to extract more performance from your 2025 Civic Si, we recommend starting with these 10 modifications first.

These 10 Performance Upgrades Make the 2025 Honda Civic Si a Solid Sports Sedan first appeared on Autoblog on Jul 12, 2025

This story was originally reported by Autoblog on Jul 12, 2025, where it first appeared.