don't you have the wrong calibration currently? setting your fuel pressure to bring the BLMs in is a bandaid fix at best and fools errand IMO. Vortec or TPI pump is an excellent upgrade even on a bone stock setup. 13 psi, again is fine on stock stuff and where i target on stock or lightly modified.
is your engine a 350 or 305? is a stock TBI motor or originally a carb'd engine? previously you stated you had 350 injectors. are these GM used or aftermarket?
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