Need Help Understanding the Impact of Various Turbine Wheels

[Scottie-GNZ]

The 52, 54, 60, 61 & 62 turbos all use the same T04B 60-1 compressor wheel, but each uses a different turbine wheel. It is pretty straight-forward to estimate pressure ratio and flow and see how those plot on a compressor map. However, we know all those turbos are not equal so the difference must be the turbine side. How does the various turbine wheels impact turbos using the same compressor wheel, HP-wise, spoolup, driveability, etc? How would each of those spool relative to each other and to a 51?

TIA

 

[ijames]

This was briefly discussed a month ago, and no one had any quantitative way to compare turbos. In order of increasing turbine wheel size they go 60, 52, 54=61, and 62. A small turbine wheel will spool quicker but may not provide enough drive power to the compressor wheel to get to the highest flow/pressure ratio parts of the compressor map. However, like I said, I don't know a quantitative way to say that this turbine will and that turbine won't. That's why we pay guys like Harry and John Craig to build and test combos for us . Oh, besides being able to get to higher boosts, a bigger turbine will provide the same drive power with less backpressure for better efficiency so it can flow the same air at lower boost compared to a smaller turbine.