Turbo question

[specialagentPK]

So I am hauling a loader today and start thinking about turbos.

Let me give you the scenario.

Turbo A has lets say for this a 70mm compressor wheel. For the inducer (I believe it is called this) wheel I don't know sizes but lets say it is smaller than turbo B

Turbo B has a 70mm compressor wheel and a larger inducer than turbo B.

Givin that the 70mm compressor won't go out of its map:

Turbo A should have a quicker spool up time but higher drive pressure which would mean higher egt's if the boost is the same as turbo B

Turbo B will have a slower spool up time but lower drive pressures and have more top end and lower egt's at a given boost that is the same as turbo A.


Is my thinking correct or is there something wrong with it?

 

[McRat]

The bigger the inducer gets in relation to the exducer (major dia), the more potential the charger has for high pressure ratios, but the narrower the map.

Picture you "bite" one inch of air with a blade, you compress it down to 1/4", you have 4:1 PR. But you must work it harder to do it.

Or you "bite" a 1/2" of air and compress it down to 1/4". 2:1 PR, but very easy to compress.

Think of it as "leverage". Too big of lever is harder to use, too small is easy to use, but doesn't have much force.

Is that the question?