Transform your Acura NSX with the Innovative Mounts 81550 K-Series Engine Swap Mount Kit, engineered for installing compatible Honda K-Series engines and K20-style manual transmissions into the 1990–2005 Acura NSX NA1 and NA2 chassis.

Designed for enthusiasts looking to replace the factory C30A or C32B V6 drivetrain with Honda's versatile K-Series engine platform, the Innovative Mounts 81550 provides the specialized engine and transmission mounting components required for a properly configured K-swap.

The Honda K-Series platform offers excellent aftermarket support, extensive tuning capabilities, and strong naturally aspirated and forced-induction performance potential. Whether you're building a high-revving K20-powered NSX, a turbocharged K-Series track car, or a custom K24-powered project using a compatible K20 transmission, the 81550 provides a purpose-built mounting foundation.

Featuring durable steel construction, CAD/CAM-engineered mounting geometry, stress-analyzed components, and Innovative Mounts' no-tear polyurethane bushings, this kit is designed to provide increased drivetrain rigidity while maintaining proper engine placement within the NSX chassis.

The Innovative Mounts 81550 is a three-mount conversion system designed for compatible K-Series engines and manual K20 transmissions. An optional front engine mount is available separately for builders requiring additional drivetrain support.

Designed for Acura NSX K-Series Engine Conversions

The first-generation Acura NSX is known for its mid-engine layout, lightweight aluminum chassis, and exceptional handling characteristics.

The Innovative Mounts 81550 allows builders to replace the factory V6 powertrain with a compatible Honda K-Series engine and manual transmission combination.

Key benefits include:

• Application-specific mounting for the 1990–2005 Acura NSX.

• Compatible with NA1 and NA2 chassis configurations.

• Supports compatible Honda K20 engine conversions.

• Accommodates compatible K24 engines when using the correct engine-side post mount.

• Designed for K20-style manual transmissions.

• Durable steel mounting components.

• Three-position engine and transmission mounting system.

• Performance polyurethane bushings.

• Reduced excessive drivetrain movement.

• Improved engine and transmission stability.

• Optional front mount available separately.

• Multiple bushing hardness options.

K20 and K24 Engine Compatibility

The Innovative Mounts 81550 is designed primarily for Honda K-Series engine conversions using a compatible K20 manual transmission.

Popular K20 engine candidates include:

• Honda K20A

• Honda K20A2

• Honda K20Z1

• Other compatible K20 configurations

The kit can also accommodate compatible K24 engine blocks when paired with the proper K24A1 engine-side post mount and a supported K20 manual transmission.

This allows builders to take advantage of the additional displacement and torque potential offered by the K24 platform.

Important: The 81550 does not support K24-style manual transmissions from the Honda Accord, Acura TSX, or Accord Euro R. K24 engine compatibility does not mean K24 transmission compatibility.

K20 Manual Transmission Compatibility

The Innovative Mounts 81550 is engineered around compatible K20 manual transmission mounting configurations.

These transmissions are commonly associated with performance-oriented Honda and Acura K-Series applications.

Potential donor applications include compatible manual transmissions from:

• Acura RSX Type-S

• Honda Civic Si

• Other supported K20 manual transmission configurations

Exact compatibility depends on the transmission case, mounting provisions, engine-side brackets, and selected engine combination.

Precision-Engineered Steel Construction

Innovative Mounts manufactures the 81550 using durable steel mounting components designed for performance applications.

CAD/CAM engineering and stress analysis help provide consistent fitment, proper drivetrain positioning, and dependable mounting strength.

The mounting system is engineered to provide maximum rigidity and ideal engine placement within the NSX chassis.

No-Tear Performance Polyurethane Bushings

The Innovative Mounts 81550 incorporates performance polyurethane bushings designed to minimize excessive drivetrain movement.

Compared with conventional rubber or fluid-damped mounts, polyurethane provides increased resistance to engine rocking during acceleration, deceleration, and shifting.

Benefits include:

• Reduced excessive engine movement.

• Improved drivetrain stability.

• More consistent engine and transmission positioning.

• Reduced mount deflection under load.

• Improved drivetrain responsiveness.

• Potential reduction in wheel hop.

• Increased resistance to drivetrain movement.

• Multiple available bushing hardness options.

Optional Front Engine Mount

The standard Innovative Mounts 81550 includes the side and rear mounting positions.

A front engine mount is available separately for builders requiring additional drivetrain support.

An additional front mount may be beneficial for aggressive performance applications where increased resistance to engine movement is desired.

Important: The optional front mount is not included with the standard 81550 kit.

Features

• 1990–2005 Acura NSX Compatibility: Designed for first-generation NA1 and NA2 chassis applications.

• K-Series Engine Swap Design: Supports compatible Honda K-Series engine conversions.

• K20 Manual Transmission Compatibility: Engineered for supported K20-style manual transmissions.

• K24 Engine Support: Accommodates compatible K24 engines when using the required K24A1 post mount and K20 manual transmission.

• Three-Mount Configuration: Includes the side and rear engine mounting positions.

• Steel Construction: Durable mounting components engineered for performance applications.

• CAD/CAM Engineered: Designed for accurate fitment and consistent manufacturing quality.

• Stress-Analyzed Components: Developed for demanding drivetrain applications.

• No-Tear Polyurethane Bushings: Help minimize excessive engine and transmission movement.

• Optimized Engine Placement: Designed to position the K-Series drivetrain within the NSX chassis.

• Increased Drivetrain Rigidity: Helps reduce excessive engine rocking during acceleration.

• Improved Throttle Response: Reduced mount deflection can improve drivetrain responsiveness.

• Optional Front Mount: Additional front engine mounting support available separately.

• Multiple Bushing Hardness Options: Available in 75A, 85A, and 95A polyurethane configurations.

• Street and Motorsport Applications: Suitable for properly configured performance builds.

• Lifetime Warranty: Backed by Innovative Mounts' lifetime warranty, subject to manufacturer terms.

Popular Performance Applications

K20-Powered Acura NSX Builds

Provides specialized mounting support for compatible K20 engine conversions.

K24-Powered Acura NSX Projects

Supports properly configured K24 engines when paired with the required K24A1 post mount and compatible K20 manual transmission.

Naturally Aspirated K-Series Performance

Suitable for compatible engines equipped with upgraded camshafts, intake manifolds, headers, and other naturally aspirated performance components.

Turbocharged K-Series NSX Builds

Performance polyurethane bushings help control excessive drivetrain movement in properly configured forced-induction applications.

Track and Road Racing

Provides increased drivetrain stability during aggressive acceleration, braking, and cornering.

Drag Racing Applications

Firmer polyurethane bushings help reduce unwanted engine movement during high-load launches.

Custom Mid-Engine Honda Builds

Offers an application-specific mounting foundation for enthusiasts building a unique K-Series-powered NSX.

Additional Information

• Manufacturer: Innovative Mounts
• Part Number: 81550
• Product Type: Steel K-Series Engine Swap Mount Kit
• Vehicle Application: 1990–2005 Acura NSX
• Chassis Compatibility: NA1 / NA2
• Engine Compatibility: Compatible Honda K-Series
• Transmission Compatibility: K20-Style Manual
• K24 Engine Requirement: Compatible K24 Engine with K24A1 Post Mount
• Excluded Transmissions: K24 Accord / TSX / Euro R Manual Transmissions
• Mount Construction: Steel
• Bushing Material: Performance Polyurethane
• Available Bushing Hardness Options: 75A / 85A / 95A
• Mounting Configuration: Three-Mount System
• Optional Front Mount: Sold Separately
• Engineering: CAD/CAM Designed and Stress Analyzed
• Installation Type: K-Series Engine Swap Conversion
• Warranty: Manufacturer Lifetime Warranty, Subject to Terms

Available Polyurethane Bushing Hardness Options

75A – Black – Street / Performance

The softest available option for the 81550.

Designed for performance-oriented street vehicles where improved drivetrain stability is desired while retaining some vibration isolation.

Manufacturer horsepower guidance: approximately 250–400 HP.

85A – Grey – Performance / Race

Provides increased drivetrain rigidity for modified engines, aggressive driving, and competition applications.

Manufacturer horsepower guidance: approximately 400–500 HP.

95A – Red – Extreme Race

The stiffest available polyurethane option, intended for high-output engines and dedicated racing applications.

Manufacturer horsepower guidance: 500+ HP.

These horsepower ranges are general manufacturer selection guidelines rather than guaranteed load ratings.

Important: Firmer polyurethane bushings generally increase noise, vibration, and harshness transmitted into the vehicle cabin.

Common Reasons for Replacement or Upgrade

• K-Series Engine Conversion: Provides specialized mounting components for installing a compatible Honda K-Series drivetrain into the Acura NSX.

• K20 Manual Transmission Installation: Designed around supported K20-style manual transmission configurations.

• K24 Engine Conversion: Supports compatible K24 engine installations with the required K24A1 post mount.

• Improved Drivetrain Stability: Helps reduce excessive engine movement during acceleration.

• Reduced Mount Deflection: Provides firmer engine support compared with conventional rubber mounts.

• Improved Drivetrain Response: Helps maintain consistent engine positioning under load.

• Performance Engine Builds: Suitable for compatible naturally aspirated and turbocharged K-Series applications.

• Track and Racing Applications: Supports performance-oriented drivetrain configurations.

• Custom Honda Projects: Provides an application-specific mounting solution for a K-Series-powered NSX.

Installation Notes

1. Verify Vehicle Compatibility: Confirm that the vehicle is a first-generation Acura NSX within the supported model-year range.

2. Confirm Engine Compatibility: Identify the exact Honda K-Series engine being installed.

3. Verify Transmission Compatibility: Confirm that the selected transmission is a compatible K20-style manual transmission.

4. Check K24 Engine Requirements: When installing a compatible K24 engine, verify that the required K24A1 engine-side post mount is installed.

5. Plan the Complete Drivetrain Conversion: Obtain the required engine, transmission, axles, wiring, ECU, cooling system, and other supporting components.

6. Inspect Factory Mounting Locations: Check the chassis mounting points and surrounding components for damage or corrosion.

7. Support the Vehicle and Drivetrain: Use appropriate lifting equipment and engine support tools.

8. Remove the Factory V6 Drivetrain: Follow applicable Acura service procedures.

9. Prepare the K-Series Engine: Install the required engine-side mounting brackets and supporting swap components.

10. Install the Innovative Mounts Components: Position the side and rear engine mounts according to the manufacturer's installation instructions.

11. Verify Engine and Transmission Positioning: Ensure the drivetrain is properly aligned and the mounts are not binding.

12. Inspect Axle Fitment: Confirm proper axle engagement, operating angles, and clearance.

13. Check Engine Bay Clearance: Verify clearance around the subframe, exhaust system, intake components, and surrounding accessories.

14. Install the Optional Front Mount if Applicable: Additional front mounting support may be installed using the appropriate compatible components.

15. Complete Supporting Systems: Install and verify the ECU, wiring, cooling, fuel, intake, exhaust, and clutch components.

16. Torque Mounting Hardware: Follow Innovative Mounts' installation instructions and applicable Acura factory torque specifications.

17. Perform a Final Inspection: Check mounting hardware, engine clearance, fluid connections, and drivetrain operation before driving.

18. Check for Excessive Vibration: Some increase in vibration is normal with performance polyurethane mounts, particularly with firmer bushing options.

19. Recheck After Initial Use: Inspect the mounting hardware and drivetrain components after the initial driving period.

Professional installation is strongly recommended, as K-Series NSX conversions require extensive drivetrain integration and supporting modifications.

What's Included

The Innovative Mounts 81550 includes:

• Driver-side engine mounting components

• Passenger-side / transmission mounting components

• Rear engine mounting components

• Performance polyurethane bushings in the selected hardness configuration

• Select installation hardware

Important: The standard 81550 kit includes three mounting positions. The optional front mount is not included.

Additional Components Required

The following components are not included unless separately specified:

• Honda K-Series engine

• Compatible K20-style manual transmission

• K24A1 engine-side post mount, if required

• Clutch and flywheel

• Axles and intermediate shaft

• Shifter and shift linkage components

• ECU and wiring conversion components

• Cooling system modifications

• Fuel system components

• Intake and exhaust components

• Additional engine-side brackets, as required

• Optional front engine mount

• Custom drivetrain conversion components, as applicable

Closing Product Summary

Transform your Acura NSX with the Innovative Mounts 81550 K-Series Engine Swap Mount Kit, engineered for 1990–2005 NA1/NA2 applications using compatible Honda K-Series engines and K20-style manual transmissions.

Featuring durable steel construction, CAD/CAM engineering, stress-analyzed components, performance polyurethane bushings, and application-specific mounting geometry, the 81550 provides the drivetrain support needed for a serious K-Series conversion.

Whether you're building a naturally aspirated K20-powered NSX, a high-torque K24 project using the proper K24A1 post mount, or a custom turbocharged K-Series track car, Innovative Mounts delivers a purpose-built mounting solution for your build.