Garrett GT3071R Turbochargers

What the Garrett GT3071R is

The GT3071R belongs to Garrett’s original GT Series of performance turbochargers. It is a ball-bearing turbo with a water-cooled center housing (CHRA), a 53 / 71 mm compressor wheel and a 60 / 55 mm, 84 trim turbine wheel. Garrett rates it at 280 to 480 horsepower on engines of 2.5 to 3.5 liters.

Garrett sells the GT3071R as a supercore to which a turbine housing kit is added (836028-5002S and 836028-5005S, listed here as partial turbos), and its turbine kits fit GT, GTX Gen I and GTX Gen II 30-series supercores alike. The complete turbos on this page differ mainly in the turbine side: housings from 0.63 to 0.86 A/R, Audi K24/K26-flanged and Nissan RB25DET-style T3 housings, versions with the 90 trim turbine wheel (listed as GT2971R-90T), and bolt-on kits for the Ford Focus ST 2.0L EcoBoost and the Volvo C30. Garrett’s own guidance on turbine housings: a smaller A/R gives quicker boost response and more turbine power at low engine speed; a larger A/R lets the wheel flow more, with lower back pressure and more power at high engine speed.

Sources: Garrett GT3071R catalog page · Garrett: Turbine Housings 101

GT3071R specifications

Wheel sizes are inducer / exducer, taken from the specification published for each part number. The turbine housing sizes are the ones on the listings above; the same turbo is sold with several.