Garrett GTX4202R Turbochargers

What the Garrett GTX4202R is

The GTX4202R is a Garrett GTX-series turbo with a dual ceramic ball bearing cartridge, a forged, fully machined billet compressor wheel of 76 / 102 mm (55 trim) and an Inconel turbine wheel of 82 / 75 mm (84 trim). Garrett rated it at 525 to 1,120 horsepower on engines of 2.0 to 7.0 liters (1,150 hp in its 2012 catalog) and sold it as a supercore (800269-5002S) without turbine housing, for use with divided, free-float T4-inlet housings and an external wastegate; Garrett pointed it at LS engine builds among others. Garrett’s current online catalog no longer shows the GTX4202R; these figures are from its archived page.

This page lists GTX4202R turbos with T4 divided and undivided, T6 divided and V-band turbine housings from 1.01 to 1.44 A/R. 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 GTX4202R page (archived) · Garrett catalog Vol. 5 (archived PDF) · Garrett: Turbine Housings 101

GTX4202R 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.