If you own a Lexus IS series and want to boost its performance and sound, upgrading the midpipe is a popular choice. The midpipe plays a crucial role in exhaust flow, affecting both power and sound quality. Here are the top 10 midpipe upgrades for Lexus IS series owners looking to enhance their ride.

Understanding the Midpipe's Role in the Lexus IS Exhaust System

Before diving into specific upgrades, it's helpful to understand what the midpipe does. In the exhaust system, the midpipe connects the catalytic converter(s) or downpipe to the rear axle-back section. It often contains a resonator or a straight-through pipe. Upgrading the midpipe can reduce backpressure, smooth exhaust flow, and change the exhaust note. For Lexus IS models – whether the IS250, IS350, or the high-performance IS F – the midpipe is a common modification because it offers noticeable gains in both sound volume and throttle response without requiring a full cat-back system.

A well-chosen midpipe can add 5–10 horsepower on naturally aspirated engines and slightly more on turbocharged variants (though the IS series is predominantly NA except for the 2.0L turbo in later models). Sound improvement is often the primary motivation: a sportier, deeper tone with less restriction. However, it's important to match the midpipe with your existing exhaust setup – a cat-back or axle-back – to avoid drone or excessive volume.

Top 10 Midpipe Upgrades for the Lexus IS Series

Each of these brands has earned a reputation among Lexus enthusiasts. We break down construction, sound character, compatibility, and value.

1. Borla Midpipe

Borla is a household name in aftermarket exhausts. Their midpipes for the Lexus IS series are constructed from T-304 stainless steel with mandrel bends for uninterrupted flow. Borla uses an "Aero-Turbine" technology in some designs that reduces drone while maintaining aggressive notes. On the IS350, the Borla midpipe produces a deep, refined growl at idle and a full-bodied roar under wide-open throttle. Expect gains of 5–7 hp when paired with a cat-back. Prices range from $400 to $650 depending on model. Visit Borla's official site for exact fitment guidance.

2. MagnaFlow Midpipe

MagnaFlow is known for its free-flowing exhaust components. Their midpipe for the Lexus IS features CNC precision mandrel bends and a 2.5-inch or 3-inch diameter (model dependent). The core is made of 100% stainless steel with a straight-through perforated tube design that eliminates baffling for maximum flow. Sound is smooth and muscle-car inspired – not overly raspy. Many owners report improved fuel economy due to reduced backpressure. MagnaFlow midpipes are often OBD-II compliant and bolt directly to factory hangers. Starting at $350. Check MagnaFlow's application guide here.

3. Invidia Midpipe

Invidia has become a favorite for Japanese imports, including the Lexus IS. Their midpipe is typically manufactured from 304 stainless steel with a 2.5-inch diameter, featuring a straight-through design with a resonator that cancels objectionable frequencies. On the Lexus IS250, Invidia’s midpipe provides a clean, aggressive tone without overwhelming drone. Build quality is excellent, with smooth welds and consistent flanges. Dyno tests show modest but consistent gains of 4–6 hp. Invidia also offers a "Q300" variant with an additional resonator for those wanting a quieter output. Priced between $380 and $550. Invidia product page for Lexus IS.

4. Agency Power Midpipe

Agency Power provides midpipes that deliver a sporty sound and improved exhaust flow. Their products are made from high-grade stainless steel with precise craftsmanship.

5. HKS Midpipe

HKS is a trusted name in performance parts. Their midpipes are designed to increase power and give a more aggressive exhaust note for the Lexus IS series. HKS often uses a combination of stainless steel and a specialized resonator design to fine-tune sound. For the IS350, the HKS midpipe paired with the Legamax cat-back produces one of the cleanest exhaust tones available. Gains are in the 5–8 hp range. Installation is straightforward. Prices start around $450.

6. GReddy Midpipe

GReddy offers midpipes that balance performance and sound. Their products are engineered for durability and optimal exhaust flow. GReddy tends to use a slightly larger diameter tubing on V6 models to maximize scavenging. The midpipe is often part of a larger Supreme SP series, but they sell it separately. Expect a deep tone with minimal rasp. GReddy's "battleweld" construction ensures long life. Around $400.

7. Corsa Midpipe

Corsa's midpipes are designed for a refined yet sporty sound. They feature innovative "RSC" (Reflective Sound Cancellation) technology to reduce drone without needing bulky resonators. On the IS F, the Corsa midpipe eliminates the factory secondary cats and straightens the flow, producing an exotic, high-pitched wail at high RPM. Corsa uses 304L stainless steel and CNC mandrel bends. Their midpipes are on the pricier side, $600–$800, but the sound quality is among the best. See Corsa's Lexus IS lineup.

8. ARK Performance Midpipe

ARK Performance offers midpipes that maximize exhaust flow and produce a commanding sound. Their products are popular among tuners and enthusiasts. ARK uses a Y-pipe merge collector design in some applications to scavenge exhaust pulses. The midpipe is crafted from T-6061 T-6 aluminum or stainless steel depending on the series. Sound is aggressive but refined, with a characteristic European sports-car note. Gains are respectable at 5–6 hp. Priced around $500.

9. Takeda Midpipe

Takeda provides midpipes that improve throttle response and exhaust tone. Their designs focus on quality and performance enhancement.

10. Vibrant Performance Midpipe

Vibrant Performance's midpipes are known for their excellent craftsmanship and performance gains. They help achieve a deeper, more aggressive sound.

How to Choose the Right Midpipe for Your Lexus IS

Resonated vs. Non-Resonated

One of the first decisions is whether the midpipe includes a resonator. A resonated midpipe uses a baffled chamber to cancel specific frequencies, reducing drone during highway cruising. Non-resonated midpipes are simpler straight pipes that maximize flow and loudness but can introduce drone, especially on cars with manual transmissions or older automatics. For daily drivers, a resonated midpipe from brands like Invidia or MagnaFlow is often the better choice. Track or weekend drivers may prefer the raw sound of a non-resonated unit from Agency Power or Vibrant.

Material and Construction

Most quality midpipes are made from 304 stainless steel, which resists corrosion and heat. Some lower-end or non-stainless options exist but are not recommended for longevity. Mandrel bending – where the pipe maintains consistent diameter through bends – is essential for preserving flow. All the brands listed use mandrel bends. Check for smooth, clean welds and quality flanges that mate tightly to factory gaskets. Avoid midpipes that require cutting or welding unless you're planning a custom setup.

Exhaust Flow and Drone

The diameter of the midpipe should match your engine's displacement and power goals. For the 2.5L IS250, 2.25–2.5 inches is sufficient. The 3.5L IS350 benefits from 2.5–3 inches, especially if you have headers or a tune. The IS F with its 5.0L V8 can use 3 inches or larger. Going too large can sacrifice low-end torque and increase drone. Drone is a resonant bass frequency that occurs at certain RPM. A well-designed resonator (like MagnaFlow's Helmholtz style or Corsa's RSC) can eliminate drone while keeping sound aggressive.

Compatibility with Your Model and Year

Lexus IS series spans multiple generations: XE10 (1998–2005), XE20 (2005–2013), and XE30 (2013–present). Midpipe designs vary by generation because of differences in underbody layout, catalytic converter placement, and hanger positions. Always verify that the midpipe is specifically listed for your model year and engine. Many brands produce separate midpipes for the IS250, IS350, and IS F. Some midpipes also replace the secondary catalytic converter – check local emissions laws before installing.

Installation Tips and Considerations

Installing a midpipe is generally a bolt-on job for the Lexus IS if you have the right tools. You will need jack stands or a lift, basic socket set, and penetrating oil for rusted bolts. Most midpipes come with new gaskets and hardware. The process involves unbolting the existing midpipe from the downpipe or front pipe and the axle-back, transferring the oxygen sensor if the midpipe has a bung, and then bolting the new unit. Expect one to two hours of labor. If you are not comfortable working under the car, a good muffler shop can install for $100–$150.

Important: After installation, check for exhaust leaks at all joints. A small leak can cause an irritating ticking sound and reduce performance. Also, allow the exhaust to “break in” – the sound may mellow or deepen after a few hundred miles as carbon builds up inside the pipe.

Conclusion

Upgrading your Lexus IS series midpipe can significantly improve both performance and sound. Consider your specific goals—whether power, sound, or durability—when choosing the right upgrade. Always ensure compatibility with your model and consult with a professional if needed for installation. The ten brands listed above represent the best options on the market, each with its unique character. Whether you prioritize track-ready aggression or refined daily drivability, there's a midpipe that fits your Lexus IS perfectly.