"pressure drop"

I assume we are all referencing backpressure drop?

 

The way I understand it, ideally there would be no tubing whatsoever past the turbine outlet, so virtually no "backpressure", which would mean "increasing pressure drop" past the turbine outlet to an infinite value.

In that case the only exhaust pressure remaining would be the pressure built by exhaust gases flowing through turbine blades.

 

There are two different pressure drops in the turbine circuit.....one pressure drop from the engine to the turbine, one pressure drop from the turbine to atmosphere.

It doesn't make any difference which turbine, turbine volute or at what rpm, the less pressure drop (incorrectly called back pressure which seems to have currency on this board) you have after the exhaust of the turbine, the more hp.

Back pressure used on this board refers to the pressure drop in the turbine circuit which comes from the small nozzle area in a small a/r turbine.......quick spool, high pressure drop, lower power.

 

OK, so perhaps someone could dyno with a standard exhaust and then with no downpipe/exhaust in the interests of determining the change on a 951 ?.