The rating on the compressor is telling you one specific thing: How much air you can flow at a given pressure. It translates to one other thing: How good your compressor is. This is why more expensive compressors have bigger pumps or bigger tanks. If you need to flow 7 CFM @ 90 psi, but your compressor can only handle 5.9 CFM at 90 psi, it won't work right. It'll cycle constantly, and it won't have enough flow to properly operate the tool. Get it?
I ran the numbers for your motor and PSI goal. First off, your temps are in a good spot. No need for an FMIC with your setup. Your inlet CFM will be 273 (18.81 lbs/min). Your pressure ratio is 1.3 (19/14.7 psi). If you take these two values and plot them on charts for the T3 turbos that Turbonetics sells, you're *way* off the efficiency charts.
<a href="http://www.turboneticsinc.com/comp_maps/fig4.html" target="_blank">
Turbonetics Maps</a>
But, then again, more PSI means more temp, which means more CFM, yada yada. I guess I'm just surprised you're going to go to all that trouble to bolt on a turbo and then only run 4.35 psi. Seems like a small payback for all the effort. Why not just do a few necessary upgrades and run 9 psi or something?
About the BOV and the pressure reading. The two spots for BOOST pressure will be different, yes. However, we usually tap into the line by the throttle body because that is actually what the engine "sees". Also, for the BOV, you need to see VACUUM...the one by the TB gets vacuum, the one off the compressor does not. Now the line for the wastegate, that can come from a spot as close to the compressor as possible.
Get it?
Shit, we should archive this when we're done <img src="#/f/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt='
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Eric