Turbo HP ratings

[barryogen]

I'm looking at Turbos at the moment, and they seem to be rated by HP...

Now what I want to know is, how accurate are the "rated to"/"flow capacity" ratings.

Is a "flow capacity of about 350HP" going to give 350 at the absolute max?
Or are they meaning is efficient when producing X boost on a X engine?

I'm assuming they mean on pump gas too, as I've read of people getting more than the "flow capacity" rating using particular turbos(~670 from one rated "flow capacity of about 600HP") on non-pump gas(not sure what it was).

[strx7]

they are actually just the HP in regards to CFM that the compressor side will flow.

[Lith]

I'm looking at Turbos at the moment, and they seem to be rated by HP...

Now what I want to know is, how accurate are the "rated to"/"flow capacity" ratings.

Is a "flow capacity of about 350HP" going to give 350 at the absolute max?
Or are they meaning is efficient when producing X boost on a X engine?

Haha I'd take it as a general guideline. Seeing as power made is a result of so many variables a turbo can't really be rated to a peak power level. Most of the Garrett/HKS turbos seem to be rated to the amount of power they are capable of flowing at ~1bar of boost on "pump gas".

Most turbos can flow more at higher boost levels, so its fair to say the power levels suggested are conservative - but again give you the rough idea of what to look for, as you don't really want to max out whatever turbo you are using anyway..... it tends to come with generating excess heat and more wear and tear.