Engine swaps in Toyota 4Runners, particularly the second generation models, have become a popular approach for enthusiasts looking to boost performance.
The LS engine series from General Motors, known for its compact design and high power output, has become a favored choice for these swaps.
Swapping an LS engine into a 2nd gen 4Runner not only offers a significant increase in horsepower and torque but also provides reliability and potential for further modifications.
The process of integrating an LS engine into a 4Runner involves extensive knowledge of both the vehicle and the engine.
It’s not just a matter of making the engine fit; it also involves ensuring compatibility with transmission, drivetrain, and the electronics system of the 4Runner.
Moreover, fabricating custom mounts, upgrading the cooling system, and making sure all components work cohesively are essential steps in the process.
Undertaking an LS swap can be a complex task, often requiring fabrication skills and a deep understanding of automotive mechanics.
However, the end result is a robust, more powerful 4Runner with the heart of an LS engine. It is something that, when done correctly, can markedly improve the vehicle’s performance and transform its driving characteristics.
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Essentials of Engine Swaps
When undertaking an LS engine swap in a 2nd gen 4Runner, it’s crucial to have a detailed game plan.
We’ll cover the fundamental choices and requirements, from understanding the basics of engine swaps to ensuring legal compliance.
Understanding Engine Swap Basics
The very first step we’ll look at is getting to grips with what an engine swap encompasses. This process involves replacing the 4Runner’s original engine with a different one, often with more power potential.
Important considerations in this phase include:
Compatibility: Ensure motor mounts and bellhousing align with the new LS engine.
Suspension: Modify as necessary to handle the new engine’s weight and power.
Transfer Case: Assess if the current 4Runner’s transfer case can handle increased torque.
Selecting the Right Engine
Choosing the correct engine for the swap involves more than just power; it’s about fit and integration.
For a 2nd gen 4Runner, the LS engine series is a popular choice for its robustness and availability. When selecting an engine, consider:
Legal Considerations and Compliance
The legality of an engine swap is essential to navigate. We must:
Check and comply with emission standards and regulations of our region.
Technical Integration in Engine Swapping
When attempting an LS engine swap into a second-generation Toyota 4Runner, integrating the new power plant with the existing vehicle systems requires careful planning and execution.
Each of the following areas must be addressed with both precision and an understanding of the systems involved.
Managing Electrical and Control Systems
The heart of an LS swap is ensuring that the engine control unit (ECU) effectively communicates with the new engine’s sensors and the 4Runner’s existing systems.
Wiring complexities arise from the integration of the LS mass airflow sensor (MAF) and the vehicle speed sensor (VSS). It’s critical to:
- Modify or replace the existing harness to fit the LS architecture.
- Utilize the correct Aisin components for seamless transmission operation.
Cooling and Exhaust Fitment
An LS engine often demands more robust cooling solutions than originally equipped.
Installing an electric fan and a larger radiator often solves the enhanced cooling needs.
For the exhaust, fitting headers and manifolds that match the LS design is essential but must also align with the 4Runner’s chassis and existing body lift, if present.
- Fabrication may be needed to fit LS-compatible headers without interference.
- Ensure sufficient clearance around the straight axle for exhaust routing to prevent heat damage.
Drivetrain and Transmission Alignment
The introduction of an LS engine to a 4Runner’s drivetrain can require substantial alterations.
Specifically, adjustments may be needed to align the engine to both the existing transmission and the drivetrain, often involving a custom adapter plate or replacement of the transmission to one that is compatible with the LS engine.
- Assess compatibility with T100 or truck transmissions for a more direct fit.
- Confirm that driveline angles are correct to avoid premature wear or failure.
| Component | Consideration | Action |
| Transmission | Compatibility with LS | Use adaptor or replace |
| Driveline angles | Prevent wear | Correct alignment |
Engine Swap Enhancements
When embarking on a 2nd gen 4Runner LS swap, it’s pertinent to focus on both performance gains and visual impact.
These upgrades are not merely about swapping engines; they are about creating a synergy between form and function that transcends the original capabilities of your 4Runner.
Upgrading for Performance
In terms of performance, an LS engine swap offers a robust increase in horsepower and torque.
To maximize this potential, we pay close attention to the supporting modifications.
Transmission and Drivetrain Upgrades:
- High-performance transmission (e.g., 700R4)
- Dana 300 transfer case
- Custom exhaust system
- Suspension and body lift modifications
Aesthetic Enhancements
Aesthetically, the LS swap shouldn’t just be a powerhouse under the hood—it should look the part too.
Therefore, we invest in aesthetic enhancements that match the engine’s boldness.
This includes fitting custom engine bay panels that complement the LS unit’s shape and installing a larger or upgraded radiator (rad) to manage the increased heat while enhancing the visual appeal.
The tachometer (tac) should be calibrated to reflect the new engine’s performance capacity.
Lastly, every attention to detail helps convey a seamless and professional swap, which might mean color-matching components or adding bespoke engine bay lighting.
Customization of the 4Runner goes beyond just the engine—it’s a holistic process that considers every visual and performance-related aspect to ensure the swap not only increases power but also presents it remarkably.
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