| 22.8psi, which we know is wrong. ((2.575PR *14.5) - 14.5) Original map: This map shows the compressor operating at 72% efficiency all the way up to about a 2.85 pressure ratio (27psi). This is very efficient in terms of the size of the wheel used (60mm major), airflow rate, and pressure ratio. These turbos have produced 30psi and make more power at this pressure than they do at 24psi. By looking at the map, it is no more/less efficient at 24psi as it is at 27psi. The turbo is operating within the same efficiency through both of these pressure ratios and airflow. When you look at 30psi (3.06 PR), it is falling into a less-efficient region (which value is unspecified on the map itself, but we know it is greater than 60%), but the cars do make more power at 30psi than they do at 27psi. This is because the losses due to less efficiency are more than overcome by the benefits of increased manifold pressure. 
Now the new map that has been published on the Honeywell website shows a compressor with significantly different flow characteristics.
It is showing a max PR of 2.6 attainable by the compressor whereas the original shows around 3.15. At 2.5PR and 13#/min of airflow, this new map says the compressor is just at its surge limit. But in the old map, the compressor is WELL into surge. This new map only shows a maximum airflow of about 35.5#/min, but the old map shows the compressor is capable of moving 37#/min. These maps show what the compressor wheel is capable of doing in any given PR and airflow, and it shows the efficiency at which it will flow these rates. If the map doesn't show it, it means the compressor isn't capable of doing it. Example: On the new map, look at the point of 2.7 P.R and 30#/min. That point isnt covered by the map, which means the compressor is physically incapable of providing air at that level. However, on the original map, not only does it tell you that it will do it, but it will also do it with excellent efficiency (72%). What I am getting at here is these maps are very different from each other - they aren't even close. We know the GT28RS will produce 30+psi, but the new map says that it is an impossibility. Something is amiss in their map, or, they have changed the design of the wheel and have something other than what they used to sell as the 62-trim wheel. 
I dont know the answer to what is going on here - I only see a discrepency in the map they show and what I have seen these turbos do. Do you know if they changed the 62-trim compressor wheel (perhaps blade count, blade orientation?) and the original 62-trim is no longer available? Or is this new map just plain wrong? This map looks an awful lot like the GT28R - someone at Honeywell screwed up when they labeled that map.
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According to the new map, the turbos can't make more than - 
