I posted this site in a reply to another post, but wanted to post it again here so you guys could check it out...

http://www.turbofast.com.au/turbomap.html

Helps you match compressor maps to your engine. Enjoy! :thumbsup

Ok, so i was playing around with this calculator and was wondering if i was reading these compressor maps right...

The center "island"? on the map is where the compressor is most efficient ?

Is it best to have the compressor matched to the engine so that it spends as much time as possible operating in the peak efficiency island?

what are realistic efficiency ratings for popular turbos , i'e the ones included in the turbo kits offered by the 3 turbo kit companies (HRC/STAR/NER)? My current inclination is to the t3/t4 s-trim bb turbo in the NER 1F kit.