pt94 is it too big for the street?
~127/111 G or ~127/106 F
Compare that to
Gt55 turbine is 112/102
The large s400 turbine many run at 96/88
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((Minor Diameter/Major Diameter)^2) *100
The G trim is 76 and the F trim is 69.
Keep in mind that on the compressor wheel the inducer is the smaller diameter and the exducer is the larger diameter but on the turbine wheel it's reversed.
The trim affects the shape and weight of the wheels. On a compressor wheel a higher trim means the wheel is able to scoop up more air to force into the engine which makes for a faster spool time but can also lead to surging where the compressor is moving too much air low speed. On the turbine wheel higher trim will also help with faster spool but will limit the amount of exhaust gases which can pass through the turbine housing. You also have to take into account that increasing the trim of a wheel also increases the weight since you're effectively adding material to it. This will also have an effect on spool times since more weight takes more energy to move (yeah physics!).
The AR is another ratio that is harder to explain but for all intents and purposes it's the size of the actual housing. Bigger housing = more flow but less gas velocity to drive the turbine and visa versa.
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