2001-2005 Lexus IS300 Headers for 3.0L 2JZ-GE
Build a stronger exhaust foundation for your naturally aspirated inline-six with a stainless-steel tubular setup designed to support smoother flow, a more purposeful exhaust note, and future exhaust-system upgrades. These Flashark headers use a 2 x 3-1 layout developed for 2001-2005 Lexus IS300 models equipped with the 3.0L 2JZ-GE DOHC engine.
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Stainless-steel construction
Mirror-polished tubing with TIG-welded CNC-machined flanges -
2 x 3-1 design
Individual primary tubes merge through dual 3-into-1 collectors
Header Specifications
| Brand | FLASHARK |
|---|---|
| Model reference | EH28653 |
| Material | Stainless steel |
| Finish | Mirror polished |
| Tube layout | Dual 3-into-1 collectors (2 x 3-1) |
| Listed connection size | 2.25-inch inlet / 2.25-inch outlet; confirm measurement locations against your exhaust before installation |
| Flanges | CNC machined and TIG welded |
| Sensor provisions | Pre-welded O2 sensor bungs |
What Is Included
- One complete exhaust-header set
- Three gaskets
- Three nuts
- Components shown in the selected product-variant photos
Package contents differ between the Exhaust Header and Exhaust Header + Catback with Muffler Tip variants. Confirm the selected variant before checkout.
What Changes After Installation?
Exhaust flow and response
Individual stainless-steel primary tubes and 3-into-1 collectors are designed to support smoother exhaust flow. Actual horsepower and torque changes depend on the vehicle's condition, complete exhaust system, intake, ECU calibration, fuel and test method. No fixed power gain should be assumed without a configuration-matched dyno test.
Exhaust sound
A tubular header can change the 2JZ-GE exhaust note, especially under acceleration. Final volume and tone depend on the complete exhaust system, including the mid-pipe, resonator, catalytic converters and catback.
Header versus factory manifold
The original cast manifold prioritizes factory durability, noise control and production requirements. A tubular header uses separate primary tubes to manage exhaust flow before the collectors. The correct choice depends on the vehicle's configuration and intended use.
Installation Notes
The header is designed as a bolt-on component for a compatible, stock-configuration vehicle and includes O2 sensor bungs and gaskets. Custom welding is not normally expected, but seized fasteners, previous exhaust modifications, damaged studs, chassis differences or non-stock piping can change the work required.
- Professional installation is recommended.
- Inspect all flanges, gaskets, studs and O2 sensor wiring before assembly.
- Check steering, chassis and heat-sensitive component clearance before final tightening.
- Recheck fastener torque and inspect for exhaust leaks after the first heat cycles.
Fitment & Compatibility
⚠️ CRITICAL FITMENT RULE (MUST READ BEFORE PURCHASE)
✅ Verified Fitment
| Brand | Model | Year Range | Full Compatible Specs |
| Lexus | IS300 | 2001-2005 | 3.0L 2JZ-GE DOHC Inline-6 Engine / Chassis Code: XE10 / Alias: Toyota Altezza |
Before purchase: confirm the year, engine code and existing exhaust configuration. Engine-swapped or previously modified vehicles should be verified with Flashark fitment support before ordering.
2001-2005 Lexus IS300 Header FAQs
Q1: Which Lexus IS300 models are listed for this header?
A1: The listed application is the 2001-2005 Lexus IS300 with the naturally aspirated 3.0L 2JZ-GE DOHC inline-six. Confirm the engine and existing exhaust configuration before purchase. Engine swaps and modified exhaust systems require additional verification.
Q2: Does the header include oxygen-sensor bungs?
A2: Yes. The product details list pre-welded O2 sensor bungs. Confirm sensor locations and wiring reach against the vehicle before installation.
Q3: What tube layout does this header use?
A3: The product is listed with a 2 x 3-1 layout: two groups of three primary tubes merge through two 3-into-1 collectors.
Q4: What connection size is listed?
A1: The original specifications list 2.25-inch inlet and outlet sizes. Because the measurement points are not defined, compare the supplied dimensions and photos with the vehicle before installation.
Q5: Can it be paired with a catback exhaust?
A5: The page offers a header-plus-catback variant, but compatibility with a different factory or aftermarket system should be confirmed using connection style, diameter and mounting locations.
Q6: How much horsepower will it add?
A6: There is no responsible universal number. Gains vary with the rest of the vehicle and the test method. Use a before-and-after dyno on the same vehicle and under comparable conditions to measure the result.
Q7: Will it improve fuel economy?
A7: No specific MPG improvement is guaranteed. Driving style, ECU behavior, exhaust configuration and vehicle condition can outweigh any change in pumping loss.
Q8: What comes in the header package?
A8: The listed header package includes one header set, three gaskets and three nuts. Confirm the selected variant because the header-plus-catback option contains different components.