looking for proper fuel pressure setting for the carbed turbo setup


Jun 5, 2001
Were setting up an 80 turbo Buick swap into my son's 88 Ranger and while researching, I cannot seem to find the incoming fuel pressure needed for this carb. I know that the Ranger has a pair of electric fuel pumps, and we have deleted the high pressure (40 psi) pump from the system. It also has a brand new low pressure in-tank pump and pickup assembly that runs up to 9/10 psi as a pickup pump. We will be plumbing it this weekend with a draw and return line to the stock mechanical pump on the 85 Buick 3.8 block. I know I want to put a fuel pressure regulator in the hard line between the mechanical pump and the carb, but don't want to overflow the carb with too much pressure. This is basically a stock rebuild on a 140 block with the internals from the 80 Monte Carlo turbo setup, nothing crazy. (My brother found out the hard way that the low pressure electric pumps on carbs need regulators on his 71 Bronco build and we don't want a repeat of his overflow/small fire!) First gen Rangers w/ carbed motors called for 4.5-9psi and we are looking for info to set this up with the correct pressure to not starve the motor while still not overwhelming the float. Thanks for any info/advice you all can give.
Not finding any Turb0-guru and turbo-specific info, what I've been able to 'glean from the interwebs' is either 4-5psi or 6-7psi. Seems that most seem to have a bit of a problem @9+ generically on these carbs. So there's where we'll start.