Lexus GX400 GX460 Supercharger Kit: Luxury SUV Power

Quick Summary: The Lexus GX is a luxury SUV built on Toyota's LandCruiser Prado platform — refined on-road, genuinely capable off-road, and powered by either the 1GR-FE 4.0L V6 (GX400) or the 1UR-FE 4.6L V8 (GX460). Both engines deliver smooth, dependable power in stock form, but neither was calibrated for a vehicle loaded with roof racks, aftermarket armour, and 33-inch tyres. AME Motorsport offers bolt-on supercharger kits for both platforms — VT Eaton TVS and HKS options for the GX400, and an HKS kit for the GX460 — delivering substantial power gains with water-cooled intercooling, dedicated cooling systems, and a 3-year warranty. No cutting, no welding, and no sacrifice to the refinement that defines the GX.

Luxury and Power Are Not Mutually Exclusive

The Lexus GX occupies a unique position in the market. It shares its body-on-frame architecture, transfer case, and axle components with the Toyota LandCruiser Prado — one of the most proven off-road platforms ever produced — but wraps that capability in leather, wood trim, and the kind of NVH engineering that makes a Lexus a Lexus. Owners choose the GX because they want genuine off-road ability without giving up highway comfort, cabin refinement, and the prestige of the Lexus badge.

The problem is power. Or, more precisely, the lack of it once the vehicle is built for serious use.

A stock GX400 produces approximately 270hp from its 1GR-FE 4.0L V6. The GX460 makes roughly 301hp from its 1UR-FE 4.6L V8. Those numbers are adequate for an unladen vehicle on smooth roads. But GX owners do not leave their vehicles unladen. They fit steel bumpers, rock sliders, roof racks, skid plates, and recovery gear. They upgrade to heavier all-terrain tyres. They tow trailers. Every kilogram added widens the gap between available power and what the loaded vehicle actually demands.

Aftermarket intake and exhaust modifications on a naturally aspirated engine yield marginal returns — typically 5 to 15 horsepower. That is not enough to offset 150 to 250 kilograms of aftermarket accessories and the increased rolling resistance from larger tyres. Forced induction is the only realistic path to meaningful power gains that preserve the GX's character.

The critical advantage of a supercharger over a turbocharger on this platform is refinement. The GX is not a vehicle where sudden boost spikes and turbo lag belong. A mechanically driven supercharger delivers smooth, linear power from just above idle through to redline — matching the progressive throttle response that Lexus engineers intended. You gain substantial power without changing the way the vehicle feels to drive. It simply has more of everything, delivered the same way.

GX400 Supercharger Kits: VT Eaton TVS and HKS Options

The Lexus GX400 uses the same 1GR-FE 4.0L V6 found in the LandCruiser Prado, Toyota 4Runner, and FJ Cruiser. This is a well-understood platform with a cast-iron block, forged crankshaft, and an engineering margin that comfortably accommodates forced induction. AME Motorsport offers two supercharger architectures for this engine.

VT Eaton TVS Supercharger Kit

The Lexus GX400 VT Supercharger Kit is built around the Eaton TVS (Twin Vortices Series) positive-displacement supercharger. This is the same proven platform used across the full range of AME Motorsport 4.0L kits, including the LandCruiser Prado 4.0 VT Supercharger Kit.

The TVS unit is a roots-type blower with four-lobe rotors that provide consistent boost from just above idle through to redline. It is mechanically driven from the crankshaft via a belt drive system. There is no lag, no dead spot in the power band, and no sudden torque spike. Boost is available the instant you open the throttle — exactly the kind of progressive, predictable power delivery that suits a luxury SUV.

With the VT Eaton kit installed, the GX400's 1GR-FE produces power equivalent to approximately a 5.7-litre engine — from a 4.0-litre displacement. The result is a vehicle that pulls harder from every speed, holds highway gears under load, and climbs steep terrain with genuine authority. You get the output of a significantly larger engine without the weight, fuel consumption, or complexity of an engine swap.

What's in the VT Kit

The complete kit includes everything required for a bolt-on installation:

• Eaton TVS supercharger unit with 3-year Eaton warranty
• Water-cooled intercooler system — reduces intake charge temperatures for consistent, safe power output
• Dedicated oil cooling system — maintains supercharger lubrication independent of engine oil
• CNC-machined mounting brackets — engineered specifically for the GX400 engine bay
• Belt drive system — complete serpentine arrangement with tensioner
• Silicone hoses and clamps — high-temperature-rated throughout
• All necessary hardware and fittings — gaskets, fasteners, and coolant lines included

Important: ECU tuning is not included in the supercharger kit. Engine management calibration must be handled separately to match your specific fuel type, altitude, and modifications. This is intentional — a tailored tune ensures optimal power delivery, fuel economy, and engine protection rather than a generic one-size-fits-all calibration.

HKS Centrifugal Supercharger Kit

The Lexus GX400 HKS Supercharger Kit offers an alternative forced induction path for the 1GR-FE. The HKS unit uses a centrifugal supercharger design rather than the positive-displacement architecture of the VT Eaton kit.

The centrifugal design produces boost that builds progressively with engine speed. At lower rpm, boost is modest. As engine speed climbs through the mid-range and toward redline, boost increases proportionally. This creates a power curve that feels more like a naturally aspirated engine with significantly more top-end — smooth and predictable, but with the peak gains arriving higher in the rev range.

For GX400 owners who spend most of their time on the highway and prioritise top-end power and overtaking ability, the HKS centrifugal kit is a strong option. For those who need maximum low-rpm torque for towing, off-road crawling, and loaded driving, the VT Eaton TVS positive-displacement kit is typically the preferred choice.

Both kits are bolt-on systems with water-cooled intercooling and 3-year warranties. Both require separate ECU tuning.

GX460 Supercharger Kit: HKS for the 1UR-FE V8

The Lexus GX460 is powered by the 1UR-FE 4.6L V8 — a naturally aspirated unit producing approximately 301hp and 446Nm in factory trim. The V8 delivers smooth, refined power that suits the GX460's luxury character, but like the V6 in the GX400, it was calibrated for a stock-weight vehicle. Loaded and lifted, the GX460 benefits significantly from additional power.

AME Motorsport offers the HKS supercharger kit for the GX460's 1UR-FE V8. This centrifugal supercharger system is a bolt-on package that adds meaningful horsepower and torque across the rev range. The centrifugal design complements the V8's existing torque curve — the 1UR-FE already produces strong low-end torque from its 4.6 litres of displacement, and the HKS unit layers additional power on top as engine speed rises.

For GX460 owners who have also considered the Lexus 5.7 VT Supercharger Kit for the larger 3UR-FE V8 platform, the HKS kit for the 1UR-FE offers a similar philosophy — extracting significantly more performance from the existing engine without the cost, weight, and complexity of an engine conversion.

The HKS GX460 kit includes water-cooled intercooling, is a complete bolt-on system with no cutting or welding required, and is backed by a 3-year warranty. ECU tuning is not included and must be sourced separately.

GX Supercharger Kit Comparison

Installation and Cooling Design

All three GX supercharger kits are engineered as bolt-on systems. No cutting, welding, or permanent modification to the chassis, engine, or bodywork is required. A competent workshop can complete the installation in a day, and the kits can be removed to return the vehicle to factory specification.

Water-Cooled Intercooling

Compressing air generates heat. Hot intake air reduces power output and increases detonation risk. Every GX supercharger kit uses a dedicated water-cooled intercooler circuit to manage charge temperatures. Coolant flows through the intercooler core, extracting heat from the compressed air before it enters the intake manifold.

This design is more effective than a front-mounted air-to-air intercooler for a vehicle like the GX. At low speeds — whether in traffic, on technical trails, or idling in a carpark — there is minimal ram air flowing through the front of the vehicle. A water-cooled system maintains cooling effectiveness regardless of vehicle speed. It also avoids cutting the front bumper or blocking airflow to the factory radiator, preserving the GX's clean front-end appearance.

Dedicated Oil Cooling (VT Kit)

The VT Eaton TVS supercharger operates on its own oil supply, completely separate from the engine oil circuit. The kit includes a dedicated oil cooling system that maintains optimal lubricant temperatures during sustained high-load driving. This independent system means the supercharger does not add thermal load to the factory engine oil system.

Factory Cooling Preserved

The stock radiator, thermostat, and cooling fans remain untouched across all three kits. The supercharger's cooling systems operate independently, so factory engine cooling capacity is fully retained. This is particularly important for GX owners who drive in hot climates, tow in summer conditions, or operate at sustained low speeds off-road.

Key Benefits for Lexus GX Owners

• Equivalent to 5.7L power from 4.0L — the VT Eaton kit transforms the GX400's output without an engine swap
• Luxury-grade power delivery — smooth, linear boost that matches the refined character of the Lexus GX
• Instant throttle response — mechanically driven boost with zero lag (VT Eaton TVS)
• Strong low-end torque — available where towing, off-road driving, and loaded highway merging demand it most
• High-altitude compensation — forced induction offsets the power losses naturally aspirated engines suffer at elevation
• Bolt-on installation — no cutting, welding, or permanent modification required
• Water-cooled intercooling — effective charge cooling regardless of vehicle speed or ambient temperature
• 3-year warranty — supercharger hardware backed by manufacturer warranty coverage
• Reversible — kits can be removed to return the vehicle to stock configuration
• Multiple options — VT Eaton and HKS architectures available for the GX400; HKS for the GX460

Frequently Asked Questions

Is ECU tuning included with the supercharger kit?

No. ECU tuning is not included and must be sourced separately. This is intentional — the calibration needs to account for your specific fuel type (91, 95, or 98 octane), altitude, climate, and any other modifications on the vehicle. A tailored tune ensures optimal power output, proper fuel delivery, and long-term engine protection for your individual configuration. AME Motorsport can advise on tuning options for your specific build.

What is the difference between the VT Eaton and HKS kits for the GX400?

The VT Eaton kit uses a positive-displacement supercharger that delivers consistent boost from idle to redline, with strong emphasis on low-end torque. It includes water-cooled intercooling and a dedicated oil cooling system independent of the engine oil circuit. The HKS kit uses a centrifugal supercharger that builds boost progressively with engine speed, favouring top-end power. Both are bolt-on systems with water-cooled intercooling and 3-year warranties. For off-road and towing use where low-rpm response matters most, the VT Eaton is typically preferred. For highway-focused builds, the HKS centrifugal is worth considering.

Will the supercharger affect the GX's ride quality or cabin refinement?

No. The supercharger kits mount within the engine bay and do not alter the suspension, exhaust routing, or cabin insulation. The Eaton TVS unit in particular is engineered for quiet operation — the four-lobe rotor design minimises pulsation and noise compared to older roots-type blowers. The power delivery is smooth and progressive, matching the refined driving character Lexus owners expect. You gain substantial power without introducing harshness or vibration into the cabin.

Can the GX400 supercharger kits fit if my vehicle has aftermarket accessories?

Yes. The kits mount entirely within the engine bay using CNC-machined brackets designed for the GX platform. They do not interfere with aftermarket bumpers, light bars, roof racks, snorkels, or suspension lifts. The water-cooled intercooler design eliminates the need for a front-mounted cooler that would conflict with aftermarket bumper assemblies or obstruct airflow to the factory radiator and air conditioning condenser.

How does the supercharged GX400 compare to a naturally aspirated GX460?

The GX460's 1UR-FE 4.6L V8 produces approximately 301hp in factory trim. With the VT Eaton TVS supercharger kit, the GX400's 1GR-FE 4.0L V6 produces power equivalent to approximately a 5.7-litre engine — comfortably exceeding the stock GX460's output from a smaller, lighter powerplant. For GX400 owners who want V8-beating performance without switching vehicles, the supercharger kit is a direct and cost-effective path. GX460 owners looking for even more from their V8 can add the HKS centrifugal kit to push the 1UR-FE well beyond its factory output.

Related Supercharger Kits

The GX shares its engines with several other Toyota and Lexus models. AME Motorsport offers supercharger kits across the full platform family:

• Lexus GX400 VT Supercharger Kit
• Lexus GX400 HKS Supercharger Kit
• LandCruiser Prado 4.0 VT Supercharger Kit
• Lexus 5.7 VT Supercharger Kit
• Browse All Supercharger Kits