Turbo Assembly Kit, G42-1200, T4 Divided 1.28 A/R, Garrett P/N 879779-5012S

The Garrett G42-1200 turbo assembly kit is built for serious horsepower builds that demand both strength and precision engineering. Designed for enthusiasts pushing into four-digit power territory, this assembly pairs a high-flow compressor side with a T4 divided turbine housing for engines that need serious top-end capability without sacrificing durability. This is the turbo for builders who are done compromising and ready to commit to a platform that can handle real power.

Specifications

• Compressor Wheel Inducer: 73mm
• Compressor Wheel Exducer: 91mm
• Compressor Wheel Trim: 65
• Compressor Housing A/R: 0.85
• Turbine Wheel Inducer: 82mm
• Turbine Wheel Exducer: 75mm
• Turbine Wheel Trim: 84
• Turbine Housing A/R: 1.28
• Turbine Housing Flange: T4 Divided
• Bearing System: Ball Bearing
• HP Capacity: 1200HP
• Garrett P/N: 879779-5012S

Performance & Application

This assembly is engineered for high-output builds requiring capability up to 1200HP, making it a strong fit for serious street and race applications where big power is the goal. The ball bearing construction supports quicker spool and improved response compared to journal bearing designs, while the T4 divided turbine housing helps manage exhaust pulses efficiently on high-horsepower setups. The 1.28 A/R turbine housing is suited to builders looking to balance strong top-end power delivery with efficient turbine-side flow. This is a purpose-built unit for enthusiasts and race-oriented builds targeting big numbers rather than mild street power gains.

Frequently Asked Questions

What HP can the G42-1200 support?

This turbo assembly is capable of supporting up to 1200HP.

Is this a ball bearing or journal bearing turbo?

The G42-1200 assembly uses ball bearing construction.

What turbine housing flange and A/R does this turbo use?

It uses a T4 divided turbine housing with a 1.28 A/R ratio.

What is the compressor housing A/R ratio?

The compressor housing A/R ratio is 0.85.

For builders targeting serious four-digit horsepower with the reliability of Garrett engineering, the G42-1200 turbo assembly kit delivers the flow characteristics and bearing durability needed to get there.