TIALHSG100MM

Tial Stainless steel Vband inlet turbine housing for Borg Warner chassis turbo's equipped with the Forced Inductions 100mm inducer turbine wheel.  1.xx A/R  

When looking for the right turbocharger for your car or truck many of us are stumped by what all the numbers mean when shopping for a turbo. While compressor wheel and turbine wheel sizes are often most of the numbers to focus on, the Area Ratio, or A/R for short, of the turbine housing and compressor housing are equally important.

A/R (Area/Radius) describes a geometric characteristic of all compressor and turbine housings. Technically, it is defined as:

The inlet (or, for compressor housings, the discharge) cross-sectional area divided by the radius from the turbo centerline to the centroid of that area.

I will assume that many of you don’t want to get into the math, but want to know what this really means to you. I’ll sum it up as simple as I can: The larger the number the more flow, the smaller the number the less flow.