
Garrett G-Series II G30-825 58mm Turbocharger
PRODUCT DETAILS
The G-Series II G30-825 58mm is part of Garrett's G-Series II line, the second generation of the G-Series. Its revised compressor wheel flows up to 10 percent more air than the first-generation G-Series at peak pressure ratio and peak shaft speed, with better efficiency at high flow. To turn that extra flow into more power, the engine needs to be recalibrated. G-Series II shares its compressor and turbine housings with the first-generation G-Series, so an existing Gen I turbo can be upgraded by replacing only the center housing rotating assembly (CHRA).
Garrett rates the G-Series II G30-825 58mm for 475 to 825 horsepower on 2.0 to 3.5 liter engines.
Key Specifications
- Series — G-Series II
- Frame size — 30 frame
- Horsepower rating — 475–825 hp (Garrett rating)
- Engine displacement — 2.0–3.5 L
- Compressor wheel — 58 mm inducer, 71 mm exducer
- Turbine wheel — 60 mm inducer, 55 mm exducer
- Base boost, complete turbo — 7.3 psi (0.5 bar actuator)
- Center housing — Oil and water cooled
- Maximum turbo speed — 140,000 rpm
- Supercore part number (standard rotation) — 934117-5002S
- Supercore part number (reverse rotation) — 934121-5002S
- CHRA part number (standard rotation) — 934116-5002S
- CHRA part number (reverse rotation) — 934120-5002S
- Complete turbo part number (standard rotation, 0.83 A/R) — 934118-5003S
- Complete turbo part number (standard rotation, 1.01 A/R) — 934118-5004S
Turbine Housing Options
Each turbine housing is listed by A/R (area-to-radius ratio), inlet flange, outlet and wastegate type. "Internal" housings have a built-in wastegate; "External" housings are free-float designs that require an external wastegate.
| Garrett part number | Rotation | A/R | Inlet | Outlet | Wastegate | Divided |
|---|---|---|---|---|---|---|
| 740902-0092 | Standard | 1.06 | T4 | V-Band | External | Yes |
| 740902-0090 | Standard | 0.83 | T3 | V-Band | External | No |
| 740902-0091 | Standard | 1.01 | T3 | V-Band | External | No |
| 740902-0086 | Standard | 0.61 | V-Band | V-Band | External | No |
| 740902-0087 | Standard | 0.83 | V-Band | V-Band | External | No |
| 740902-0088 | Standard | 1.01 | V-Band | V-Band | External | No |
| 740902-0089 | Standard | 1.21 | V-Band | V-Band | External | No |
| 740902-0094 | Standard | 0.83 | V-Band | V-Band | Internal | No |
| 740902-0095 | Standard | 1.01 | V-Band | V-Band | Internal | No |
| 740902-0100 | Reverse | 0.83 | T3 | V-Band | External | No |
| 740902-0101 | Reverse | 1.01 | T3 | V-Band | External | No |
| 740902-0096 | Reverse | 0.61 | V-Band | V-Band | External | No |
| 740902-0097 | Reverse | 0.83 | V-Band | V-Band | External | No |
| 740902-0098 | Reverse | 1.01 | V-Band | V-Band | External | No |
| 740902-0099 | Reverse | 1.21 | V-Band | V-Band | External | No |
Important Information
Garrett calculates its horsepower ratings from the compressor map choke flow, which represents the potential flywheel horsepower of the turbo. Actual results depend on the engine, supporting modifications and calibration.
Garrett sets the maximum allowable speed for this turbo at 140,000 rpm. Operating above that speed can damage the turbo and cause premature failure. A turbo speed sensor (sold separately) lets you monitor shaft speed.
For race vehicles only. Not for use on public roads.
Installation and Tuning Available at Race Protocol
Turbo system design, installation and dyno tuning are available in house. Call (724) 732-8948 to discuss your build.
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