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					Originally Posted by  phoenix7
					 
				 
				I noticed my boost go down to 10psi on a 2.5" catback (now on our NA) mated to my 3" DP and midpipe from 12psi (with the 3" open cat-back single). 
			
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 Did you re-adjust the boost controller to compensate for the difference in pressure differential?  As with anything else on this and other forums, its all up to personal experience.  I can hold 25 PSI all day long to the redline on my 2.5 inch catback.  Is it optimal?  HELL NO!  At my HP level I should be more on a 4 inch exhaust.  
The thing that bothers me is that the car is STOCK.  Even a stock turbo with a pre-cat, main cat, and crappy stock exhaust system should spool faster then that.  All things being considered, I am not entirely convinced its the exhaust.  It sounds like how my car ran years ago when I thought I would be smart and wire the Twin Scroll open.