Garrett G-Series II G40-1000 62mm Turbocharger

Garrett G-Series II G40-1000 62mm Turbocharger — Select Turbine Housing

Supercore Part Number: 938272-5001S

The Garrett G-Series II G40-1000 is a standard-rotation, dual-ceramic-ball-bearing turbocharger designed for high-output street, competition, and specialty-performance applications requiring substantial airflow without moving to the larger 71mm G40 compressor. Garrett rates the G40-1000 for 500–1,000 horsepower and references engine displacements from 2.0 to 6.0 liters. Garrett horsepower ratings represent potential flywheel horsepower based on compressor capability and are not a guaranteed wheel-horsepower figure.

The G40-1000 uses a 62mm inducer and 88mm exducer compressor wheel with a 51-trim profile and 0.80 compressor-housing A/R. The turbine stage uses a 77mm inducer and 70mm exducer wheel with an 84-trim profile. This combination places the G40-1000 above Garrett’s smaller G35 frame while retaining a 62mm compressor inducer, making it particularly useful where turbine flow, exhaust-side durability, and upper-range power capability are more important than minimizing overall turbocharger size.

As part of Garrett’s G-Series II range, the G40-1000 incorporates revised compressor aerodynamics that provide up to 10 percent greater compressor flow than the corresponding first-generation G-Series unit at peak pressure ratio and peak turbocharger speed. Garrett also identifies improved efficiency at high flow rates. The G-Series II supercore retains compatibility with Garrett’s first-generation G40 compressor and turbine housings, allowing an existing standard-rotation G40 installation to be upgraded without redesigning the entire turbo system, provided the current housing configuration is confirmed compatible.

This listing is structured as a selectable-housing product. The Garrett 938272-5001S supercore is combined with one of eight verified standard-rotation G40 turbine-housing kits, or it may be purchased as a supercore only. All available housings are externally wastegated, use a V-band turbine outlet, and are offered either with an open-scroll V-band inlet or a divided T4 inlet. Garrett does not list an internally wastegated G40-1000 assembly.

RAD recommends the 1.06 A/R open-scroll V-band inlet and V-band outlet housing, Garrett part number 757707-0029, as the general catalog default. It occupies the middle of the available A/R range, avoids the manifold and wastegate-layout requirements of a divided T4 system, and provides a better balance of response and exhaust-flow capacity for typical 4.0–6.0-liter single-turbo applications than either the smallest 0.85 A/R or largest 1.19 A/R housing. Final housing selection should still be based on engine displacement, power target, exhaust-manifold design, intended turbine pressure ratio, and desired boost-response characteristics.

Key Features

• Garrett G-Series II G40-1000 standard-rotation supercore
• Garrett horsepower reference range: 500–1,000 hp
• Garrett displacement reference range: 2.0–6.0 liters
• 62mm compressor inducer and 88mm compressor exducer
• 77mm turbine inducer and 70mm turbine exducer
• Dual ceramic ball-bearing center section with steel bearing cages
• G-Series II compressor aerodynamics with up to 10 percent more flow than the corresponding first-generation G-Series compressor at peak pressure ratio and peak turbo speed
• Improved high-flow compressor efficiency compared with the first-generation G-Series configuration
• One-piece center-housing and backplate architecture
• Twin piston-ring sealing on both sides of the shaft assembly
• Machined compressor-housing port for an optional Garrett turbo-speed sensor
• Water-cooled center housing with Garrett water fittings included with the supercore
• Stainless-steel turbine housings rated by Garrett for temperatures up to 1,050°C
• Eight verified external-wastegate turbine-housing options
• Open-scroll V-band and divided T4 turbine-inlet configurations
• V-band turbine outlet on every available housing
• Center-housing-to-turbine-housing V-band connection permits full rotational positioning with Garrett non-wastegated housings
• Compatible with the standard-rotation Garrett G40 housing family listed below

Kit Includes

• Garrett G-Series II G40-1000 supercore, part number 938272-5001S
• Compressor housing, compressor wheel, center housing rotating assembly, and turbine wheel
• Garrett water fittings supplied with the supercore
• Selected Garrett G40 turbine-housing kit when a complete housing variant is ordered
• Garrett gasket kit packaged with the selected turbine-housing kit
• Supercore-only variant excludes the turbine housing

Technical Specifications

Compressor

• Compressor inducer: 62mm
• Compressor exducer: 88mm
• Compressor trim: 51
• Compressor-housing A/R: 0.80
• Compressor inlet: approximately 4.00-inch hose connection
• Compressor outlet: approximately 2.50-inch hose connection
• Maximum allowable turbocharger speed: 125,000 rpm
• Optional Garrett turbo-speed sensor kits are sold separately

Turbine

• Turbine inducer: 77mm
• Turbine exducer: 70mm
• Turbine trim: 84
• Turbine-wheel material: high-temperature nickel-based superalloy
• Turbine-housing material: stainless steel
• Turbine-housing temperature rating: up to 1,050°C
• Wastegate arrangement: external wastegate required for every listed housing
• Turbine outlet: V-band on every listed housing

Center Housing, Bearings, Lubrication, and Coolant Connections

• Bearing system: dual ceramic ball bearing with steel cages
• Center-housing construction: one-piece center housing and backplate
• Shaft sealing: twin piston rings on both compressor and turbine sides
• Cooling: water cooled
• Coolant connections: Garrett -6AN water fittings supplied with the supercore
• Oil-feed and oil-drain plumbing must be selected and fabricated for the application
• Oil pressure, feed restriction, drain sizing, and drain routing must follow Garrett’s installation requirements for the specific engine and oiling system

Available Turbine Configurations

• 0.85 A/R V-Band / V-Band — Garrett 757707-0027: open-scroll V-band turbine inlet, V-band turbine outlet, external wastegate required.
• 0.95 A/R V-Band / V-Band — Garrett 757707-0028: open-scroll V-band turbine inlet, V-band turbine outlet, external wastegate required.
• 1.06 A/R V-Band / V-Band — Garrett 757707-0029: open-scroll V-band turbine inlet, V-band turbine outlet, external wastegate required. RAD recommended general catalog default.
• 1.19 A/R V-Band / V-Band — Garrett 757707-0030: open-scroll V-band turbine inlet, V-band turbine outlet, external wastegate required.
• 0.85 A/R Divided T4 / V-Band — Garrett 757707-0032: divided T4 turbine inlet, V-band turbine outlet, external wastegate required.
• 0.95 A/R Divided T4 / V-Band — Garrett 757707-0033: divided T4 turbine inlet, V-band turbine outlet, external wastegate required.
• 1.06 A/R Divided T4 / V-Band — Garrett 757707-0034: divided T4 turbine inlet, V-band turbine outlet, external wastegate required.
• 1.19 A/R Divided T4 / V-Band — Garrett 757707-0035: divided T4 turbine inlet, V-band turbine outlet, external wastegate required.
• Supercore Only — Garrett 938272-5001S: compressor housing and complete center rotating assembly supplied without a turbine housing.

Application Notes

• This is a universal performance turbocharger and is not a vehicle-specific bolt-on assembly.
• Garrett’s 500–1,000 horsepower range is a compressor-based flywheel-horsepower reference. Actual output depends on engine airflow, fuel, charge-air temperature, exhaust-manifold design, turbine housing, boost pressure, backpressure, and tune.
• The open-scroll V-band housings are generally the simpler choice for custom single-turbo systems because they do not require a true divided manifold and paired wastegate strategy.
• The divided T4 housings should be used with a properly divided manifold and an external-wastegate arrangement that preserves the intended pulse separation. Installing a divided housing on an undivided manifold does not provide the same twin-scroll behavior.
• The 0.85 and 0.95 A/R housings prioritize earlier response and may increase turbine-side restriction as airflow and power rise. The 1.06 and 1.19 A/R housings provide additional exhaust-flow capacity at the expense of some boost response.
• The G40-1000 supercore is compatible only with the verified standard-rotation G40 housings listed in this description. Reverse-rotation housings and housings from other Garrett frame families are not interchangeable.
• Garrett G-Series II uses the corresponding first-generation G40 compressor and turbine housing interfaces, but every existing installation should be confirmed by part number before components are reused.
• No internally wastegated G40-1000 configuration is listed by Garrett. An appropriately sized external wastegate system is required.
• Turbine-inlet flange or clamp, turbine-outlet weld flange and clamp, external wastegate, oil-feed line, oil-drain line, coolant hoses, intake plumbing, charge piping, exhaust manifold, downpipe, boost-control hardware, and application-specific fasteners are not included unless separately stated.
• Garrett turbo-speed sensor kits, compressor-speed display hardware, and electronic boost-control components are sold separately.
• Final turbocharger and turbine-housing selection should be based on an engine-airflow model and the intended operating range rather than displacement or peak-power target alone.

Emissions and Competition-Use Notice

This universal performance turbocharger is intended for racing and competition applications. Vehicle modifications must comply with all applicable emissions, registration, noise, and road-use requirements. It is the purchaser’s responsibility to determine whether the product is legal for the intended vehicle and use.