[texan]

Psman32- First off, check the other discussions in my forum, there's plenty of info on the different compressor designs commonly in use today.

Secondly, I should clarify the term "compressor" as I am using it; not as an all-in-one design which compresses air internally, but one that's capable of compressing air when on an engine. And all of these designs do just that; compress air in the intake system.

By your calculated efficiency rating, I assume you are speaking of adiabatic efficiency. But in every case, this number fluctuates heavily depending upon blower design and operating RPM, so a single catch-all number simply won't be accurate. Also, the stated power consumption of each design also fluctuates greatly, Magnuson has this information on the Eaton designs available on their home site. And how much power restriction a tubocharger in the exhaust path presents is highly dependent upon turbocharger selection, exhaust system design, valve timing (speaking largely of overlap amounts here) and boost level. Put simply, there is no equation to accurately estimate HP output from a supercharged engine. Usual power increases fall in the area of 35-50% more peak horsepower, and that's about as accurate as you can really get without taking several other factors into account. But I get what you are saying, you can form a vague idea of peak power levels through some basic math.

And one last thing; there is only one type of turbocharger. There are many different forms of boost management out there (as well as overall system design), but basic turbocharger design is static.

Thanks for the added information though, it's nice to see people engaging in the discussions around here. And I'm glad people see that I haven't discussed every concept surrounding forced induction here (not by a long shot), but please understand I tried to pick out the most important and necessary info. There have been many books written solely on the subject of forced induction; trying to compress that knowledge down to a few posts is not easy to do. So keep those posts coming, just understand the difficulties I have in trying to explain what's important in these threads. Hope this helps explain things, peace.