I have a very large Holset turbo. It has the number 22 stamped inside the exhaust housing. Has a 5" v-band outlet. I found some numbers to convert the 22 to a/r but just want to confirm with you guys as well. Here is the list I found.

Turbine housing areas:

3 cm2 = 0.14 A/R
4 cm2 = 0.23 A/R
5 cm2 = 0.32 A/R
6 cm2 = 0.41 A/R
7 cm2 = 0.49 A/R
8 cm2 = 0.57 A/R
9 cm2 = 0.65 A/R
10 cm2 = 0.73 A/R
11 cm2 = 0.81 A/R
12 cm2 = 0.89 A/R
14 cm2 = 0.97 A/R
15 cm2 = 1.05 A/R
16 cm2 = 1.13 A/R
17 cm2 = 1.29 A/R
19 cm2 = 1.37 A/R
20 cm2 = 1.45 A/R
21 cm2 = 1.53 A/R
22 cm2 = 1.61 A/R
23 cm2 = 1.69 A/R
24 cm2 = 1.77 A/R
25 cm2 = 1.85 A/R

Let me know if this looks right and any other info on the turbo would be great. Thanks.

Ferhan