For over two decades, the Acura RSX Type S has held a special place in the hearts of front‑wheel‑drive enthusiasts. Its high‑revving K20Z1 engine, crisp six‑speed manual, and balanced chassis offer a driving experience that still feels engaging by modern standards. As 2024 approaches, the aftermarket ecosystem for this platform remains incredibly robust. Whether you are chasing a few extra horsepower for daily driving or building a dedicated track car, the following five performance upgrades offer the most significant gains for your RSX Type S. Each modification has been chosen for its proven impact, real‑world reliability, and compatibility with the K‑series engine family.

Before diving into modifications, it is wise to establish a baseline. Perform a thorough inspection of ignition components (spark plugs, coil packs) and ensure the timing chain is in good condition. Clean air filters and fresh oil also help the engine respond predictably to upgrades. With that foundation in place, let us explore the top performance upgrades for 2024.

1. Cold Air Intake System

A cold air intake is often the first modification RSX owners make, and for good reason. The factory airbox prioritizes quiet operation over maximum airflow. Replacing it with a well‑designed cold air intake allows the engine to draw denser, cooler air from outside the engine bay. This simple change improves volumetric efficiency, leading to a measurable increase in horsepower and a sharper throttle response.

What It Does

The intake system works by reducing the restriction that the stock airbox and intake tubing create. Aftermarket intakes typically use a larger, smoother pipe and a high‑flow conical filter. Some designs place the filter behind the front bumper or in the inner fender to pull air away from heat sources like the radiator and exhaust manifold. Cooler air contains more oxygen molecules per volume, which supports more complete combustion.

Expected Gains

On the RSX Type S, a quality cold air intake (such as the AEM V2 or Injen RD series) can add 8–12 horsepower at the wheels without requiring any other changes. The torque curve also improves in the mid‑range, making the car feel more responsive in daily driving. Most owners report a noticeably more aggressive intake sound, with the signature K‑series induction noise becoming more prominent above 4,000 rpm.

Installation and Tuning

Installing a cold air intake on the RSX Type S is straightforward. The process involves removing the factory airbox, disconnecting the intake tube and mass airflow sensor, then mounting the new filter and piping. Most kits come with detailed instructions and require only basic hand tools. No custom tuning is required for this upgrade, though it is a good idea to reset the ECU by disconnecting the battery for a few minutes.

Be aware that some cold air intake systems route the filter into the lower bumper area, which can be vulnerable to water ingestion during heavy rain or puddle driving. If you live in a wet climate, consider a short ram intake or a bypass valve. The AEM cold air intake is a popular choice because it includes a bypass valve option.

2. High‑Performance Exhaust System

After improving how the engine breathes in, the next logical step is to improve how it breathes out. The stock exhaust system on the RSX Type S is relatively restrictive, with multiple resonators and a muffler designed to keep the noise level low. Upgrading to a free‑flowing aftermarket exhaust reduces back pressure and allows the engine to expel exhaust gases more efficiently. This directly translates to higher horsepower and a more exhilarating sound.

System Components

A full exhaust upgrade typically includes a new header (or downpipe on turbocharged cars), a catalytic converter replacement or high‑flow cat, a mid‑pipe, and a cat‑back exhaust. For the NA RSX Type S, the biggest gains come from the header and the cat‑back section. Aftermarket headers with larger primary tubes and a merge collector improve exhaust scavenging, which helps the engine make more power at high rpm. A cat‑back system with mandrel‑bent piping and a straight‑through muffler reduces restriction even further.

Gains and Sound

Combining a quality header (like the Skunk2 Megaphone or PLM race header) with a 2.5‑inch cat‑back exhaust can yield 15–20 wheel horsepower. The torque increase is most noticeable in the mid‑range, and the engine revs more freely to the 8,100‑rpm redline. Sound is subjective, but the RSX Type S gains a deep, bassy note at idle that builds into a raspy scream at full throttle. Some owners prefer a resonated mid‑pipe to keep drone under control during highway driving.

Installing a header and exhaust is more involved than an intake. You will need to support the car on jack stands, apply penetrating oil to rusty bolts, and possibly remove the front sway bar for header access. Most aftermarket headers require a slight modification to the stock cat‑pipe or a separate test pipe. If your car must pass emissions testing, be sure to choose a CARB‑compliant header or retain a quality high‑flow catalytic converter. Check out RSXClub forums for specific installation tips and dyno results.

3. ECU Tune

No list of performance upgrades for the RSX Type S would be complete without addressing the engine’s electronic brain. The factory ECU calibrations are conservative to meet emissions and reliability targets. A professional ECU tune—often called reflashing or remapping—adjusts parameters such as air‑fuel ratios, ignition timing, VTEC engagement points, and fuel maps to better match modifications you have already installed. This is the single most effective way to increase power on a naturally aspirated K‑series engine.

Tuning Platforms

For the RSX Type S, the most widely used tuning solutions are K‑Pro (by Hondata) and KTuner. Both allow real‑time data logging and full control over the ECU. K‑Pro is the gold standard, offering support for launch control, flat‑foot shifting, and multiple maps that can be switched on the fly. If your RSX still has the original ECU, you can send it out to be socketed, or you can purchase a pre‑tuned ECU from a specialist like Hondata.

Gains and Customization

A well‑tuned ECU can add 15–20 wheel horsepower on an otherwise stock engine, and up to 30 horsepower when combined with intake and exhaust upgrades. More importantly, a tune smoothes out the power delivery, eliminates the factory torque dip between 3,000 and 4,000 rpm, and optimizes VTEC crossover for maximum pull. Modern tunes also include calibration for higher octane fuel, which allows more aggressive timing and further power gains.

Tuning Process

While custom dyno tuning is ideal, remote e‑tuning (where you log data and send it to a tuner) can also produce excellent results. You will need a laptop and a compatible software package. Many reputable tuners offer base maps for common combinations (intake + header + exhaust). After the initial tune, you can fine‑tune the VE tables and ignition maps to dial in every last bit of performance. Expect to spend $600–$1,000 for a complete K‑Pro setup plus tuning session.

4. Performance Camshafts

If you have already optimized the intake, exhaust, and ECU, the next step to unlock serious top‑end power is installing aftermarket camshafts. The RSX Type S’s K20Z1 engine uses dual overhead camshafts with variable valve timing (VTEC) on both intake and exhaust sides. Upgraded camshafts with more aggressive lobe profiles allow the valves to open longer and wider, increasing the volume of air that can flow into and out of the cylinders at high rpm.

Camshaft Options

For a street‑driven RSX Type S that sees occasional track duty, mild camshafts such as the Skunk2 Pro 1 or Buddy Club Spec III+ are excellent choices. These cams provide a noticeable bump in peak horsepower while keeping driveability intact. More aggressive options like the Skunk2 Pro 2 or Stage 3 cams shift the power band higher (above 5,000 rpm) and require upgraded valvetrain components (springs and retainers) to avoid valve float. You should also plan for a higher‑than‑stock redline, which often means stronger connecting rods and a balanced bottom end for sustained reliability.

Expected Gains

Paired with a proper tune and supporting modifications (intake, header, exhaust), a set of mild performance cams can add 15–25 wheel horsepower, with the peak power moving upward by 500–1,000 rpm. The car becomes noticeably faster from 5,500 rpm to redline, and the VTEC engagement feels more pronounced. Keep in mind that installation is labor‑intensive, requiring removal of the timing chain, cam gears, and valve cover. It is strongly recommended to have a competent shop perform the work unless you have experience with K‑series timing.

Valvetrain Upgrades

Even with mild cams, replacing the factory valve springs with stiffer units (such as Skunk2 or Supertech) is a wise investment. This prevents valve float at higher rpms and ensures the cam profile delivers its full effect. If you plan to rev beyond 8,200 rpm, you will also need upgraded retainers and possibly aftermarket valves. These components are not expensive relative to the overall build cost and provide peace of mind for high‑rpm abuse.

5. Upgraded Fuel System

As you add more air and advance ignition timing, the engine will require more fuel to maintain the proper air‑fuel ratio. Factory fuel injectors are sized to support stock power levels, and the stock fuel pump is adequate only up to about 230–240 wheel horsepower. Once you exceed that threshold—often with a strong combination of intake, header, exhaust, cams, and tune—the fuel system becomes a bottleneck. Upgrading the fuel injectors and fuel pump ensures the engine receives enough fuel to safely produce maximum power without leaning out.

Injector Selection

For naturally aspirated builds aiming for 250–270 wheel horsepower, 550–750 cc injectors are ideal. The DeatschWerks 550 cc or RC Engineering 550 cc are popular drop‑in replacements. They maintain good idle quality and part‑throttle behavior, especially after a proper tune. For forced induction plans, larger injectors (1,000 cc or more) will be needed, but for a NA setup, going too large can cause poor low‑rpm drivability.

Fuel Pump Upgrade

The RSX Type S uses a common G251 style fuel pump. Aftermarket drop‑in pumps like the Walbro 255 lph or AEM 320 lph provide ample flow for naturally aspirated builds. Installation involves removing the rear seat bottom and fuel pump access cover—a job that takes about an hour. No modifications to the fuel lines are required, and the pump wiring plugs directly into the factory harness.

Tuning and Safety

After installing larger injectors, you absolutely must retune the ECU to calibrate the injector flow rates and dead times. The fuel pump upgrade does not require tuning adjustments by itself, but it ensures that the fuel pressure remains stable under high‑flow conditions. A wideband oxygen sensor is strongly recommended for monitoring air‑fuel ratios during WOT pulls. Many tuners will not even begin work until a wideband is installed.

Bringing It All Together: A Suggested Upgrade Path

Jumping straight to cams and fuel system without first establishing a strong foundation can lead to frustration and inconsistent results. Here is a proven progression for the RSX Type S aiming for 250–270 wheel horsepower:

  1. Maintenance baseline: Fresh spark plugs, oil, transmission fluid, and a clean filter.
  2. Cold air intake – gains 8–12 whp, sharpens throttle response.
  3. High‑performance header and cat‑back exhaust – adds 15–20 whp, sounds great.
  4. ECU tune (K‑Pro or KTuner) – unlocks 15–20 whp on its own and optimizes every other mod.
  5. Mild performance cams + valvetrain – elevates top‑end power by another 15–25 whp.
  6. Upgraded fuel injectors and pump – keeps everything safe and enables further tuning headroom.

With this combination, your RSX Type S will comfortably deliver over 250 wheel horsepower and a significantly wider power band. The car will be genuinely quick, out‑accelerating many modern sport compacts while retaining the raw, naturally aspirated character that makes the K‑series so beloved.

Final Considerations

Before spending money on parts, research your local emissions regulations and consider the intended use of your RSX. A full build with cams and fuel system changes may require professional installation and tuning, which adds to the total cost. Budget accordingly: a basic intake + exhaust + tune package can be done for around $1,500–$2,000, while a full bolt‑on and cam setup with tuning may run $4,000–$6,000 depending on labor rates.

Also remember that increasing power amplifies the importance of supporting systems. The RSX Type S’s brakes, cooling, and tires should be upgraded as power rises. A high‑capacity radiator, performance brake pads, and a quality set of summer tires will help you safely enjoy the extra performance. Forums like RSX Zone and the K20A.org community are excellent resources for build advice and troubleshooting.

In summary, boosting your RSX Type S power in 2024 is entirely achievable with the right combination of intake, exhaust, ECU tuning, camshafts, and fuel system upgrades. Each mod works synergistically with the others to create a cohesive, reliable, and exhilarating driving experience. Choose your upgrades carefully, invest in proper tuning, and enjoy the rewarding process of making your RSX Type S faster than ever.