Cost Breakdown: How Much Does a 700 Hp Rx-7 Ls Swap Really Cost?

The RX-7 has long been a favorite among car enthusiasts, known for its lightweight chassis and rotary engine. However, as performance demands increase, many owners are considering an LS swap to achieve greater horsepower and torque. This article will break down the costs associated with a 700 HP RX-7 LS swap, providing a comprehensive overview for those interested in this project.

Understanding the LS Swap

An LS swap involves replacing the original rotary engine with a General Motors LS series engine. This swap is popular due to the LS engine’s reliability, availability, and vast aftermarket support. Achieving 700 HP requires careful selection of components and tuning.

Cost Breakdown

Here’s a detailed breakdown of the costs involved in an LS swap for a 700 HP RX-7:

  • Engine Cost: $5,000 – $10,000
  • Transmission: $1,500 – $3,000
  • Engine Management System: $1,200 – $2,500
  • Wiring Harness: $500 – $1,200
  • Exhaust System: $800 – $1,500
  • Cooling System: $600 – $1,200
  • Drivetrain Components: $1,000 – $2,500
  • Miscellaneous Parts: $500 – $1,000
  • Labor Costs: $1,500 – $3,000

Engine Cost

The heart of the swap, the LS engine, varies significantly in price depending on the model and condition. Options range from used engines to brand new crate engines. Popular choices include:

  • LS1: $5,000 – $7,000
  • LS3: $7,000 – $10,000
  • LS7: $10,000+

Transmission

Choosing the right transmission is crucial for handling the power of a 700 HP setup. Options include:

  • T56 Manual: $1,500 – $2,500
  • 4L80E Automatic: $2,000 – $3,000

Engine Management System

A reliable engine management system is essential for tuning the LS engine to achieve optimal performance. Popular choices include:

  • HP Tuners: $1,200 – $2,500
  • EFILive: $1,500 – $2,000

Wiring Harness

A custom wiring harness is necessary to integrate the LS engine with the RX-7’s electrical system. Costs can range from:

  • Pre-made Harness: $500 – $800
  • Custom Harness: $800 – $1,200

Exhaust System

Upgrading the exhaust system is vital for maximizing performance and achieving the desired sound. Options include:

  • Headers and Mid-Pipe: $800 – $1,200
  • Full Exhaust System: $1,000 – $1,500

Cooling System

To keep the LS engine running cool, an upgraded cooling system is required. This includes:

  • Radiator: $300 – $600
  • Cooling Fans: $200 – $400

Drivetrain Components

To handle the increased power, upgrading the drivetrain components is essential. This may include:

  • Differential: $500 – $1,000
  • Axles: $500 – $1,500

Miscellaneous Parts

Additional parts such as mounts, adapters, and hardware can add up quickly. Budgeting for these components is crucial:

  • Engine Mounts: $200 – $400
  • Transmission Mounts: $100 – $200

Labor Costs

If you’re not performing the swap yourself, labor costs can be significant. Depending on the shop and complexity of the swap, expect:

  • Hourly Rate: $75 – $150
  • Total Labor Cost: $1,500 – $3,000

Conclusion

In total, the cost of a 700 HP RX-7 LS swap can range from approximately $12,000 to $25,000 or more, depending on the choices made throughout the process. It’s essential to plan carefully, budget accordingly, and research each component to ensure a successful swap that meets your performance goals. Whether you’re a DIY enthusiast or planning to hire professionals, understanding these costs will help you make informed decisions.