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G Series II Expands Into Mid Frame Power
Six new mid frame turbochargers engineered for extreme airflow, elevated pressure ratios, and serious horsepower.
Garrett Motion has officially expanded its next generation G Series II performance turbocharger line, adding six new mid frame turbos to complement the G25, G30, and G35 models. The latest additions are designed for high horsepower, high pressure applications where efficiency and airflow matter.
New Mid Frame Models
G40 1250
G42 1325C
G42 1325
G42 1585
G45 1610
The Power of Legends. The Durability of Champions.
For more than 40 years, Garrett has powered legends of motorsport from endurance racing to top tier competition, including Le Mans winners across the last 25 consecutive years. Behind that track record is a global engineering team of over 1,300 experts across five R and D centers, ensuring every product delivers performance and reliability.
G Series II brings that same motorsport DNA to kit makers, fabricators, and high performance vehicle owners, offering a universal turbo solution engineered to match the most demanding builds.
Engineering Advancements
While G Series II turbos retain the same compressor and turbine housings as Gen I, the gains come from a redesigned CHRA.
Direct Upgrade Path from Gen I
A CHRA swap transforms existing Gen I units into their Series II counterparts.
| Gen I | G Series II |
|---|---|
| G40 900 | G40 1000 |
| G40 1150 | G40 1250 |
| G42 1200 | G42 1325 |
| G42 1200C | G42 1325C |
| G42 1450 | G42 1585 |
| G45 1475 | G45 1610 |
View G Series II Turbochargers
Compressor Map Overlays
Overlay convention: Gen I is red. G Series II is black.
How to Read These Maps
- Axes: X is mass flow (lb per min). Y is pressure ratio.
- Efficiency islands: the center region represents highest efficiency.
- Turbo speed lines: tighter spacing near the right edge indicates overspeed risk.
- Rule of thumb: about 10 to 11 flywheel hp per 1 lb per min of airflow.
- Surge line: unstable flow region. A bypass or BOV can help avoid surge conditions.
- Choke line: rapid efficiency drop and overspeed risk. If operating here, consider a larger compressor.
- Max speed: do not exceed maximum turbo speed.
Why These Gains Matter
The new CHRA aero increases compressor efficiency where modern high output builds operate: elevated pressure ratios, extended RPM, and sustained pulls where charge air temperature control is critical. The result is more power potential for the same boost, or the same power with less heat and less effort. Both outcomes support durability and repeatability.
Designed for Builders and Enthusiasts
Whether you are developing a new turbo kit or upgrading an existing high performance build, the G Series II line now spans from G25 through G45 and covers a wide spectrum of power levels.
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