I've been looking around at the rail mounted FPRs and I've noticed they are all different lol. Some say they are 50psi, some are 52. the highest that I've seen is 56.56 PSI. Is there one that is 58psi like the stock one should be? I'm only getting 52-53 psi at idle with the vacuum line off.

 

Adjust it with the set screw.

 

its non adjustable
I found this one
2001 GMC Sierra C3 Fuel Pressure Regulator - Fuel Injection - Accel 01 Sierra C3 Fuel Pressure Regulator - 4271-03000388 - PartsGeek
But not really sure if it will fit and how much its adjustable

 

Heres something cool...it doesnt really matter what the rail pressure is (as long as the injectors can behave at low pulse widths). You can adjust the IFR table to your new pressure.

 

If it doesn't adjust then you better do what Richard said.

 

I may have to try that. Ill have to see what the new injectors can do first.
would changing the ifr table help with the high rpm fuel delivery?

 

No it doesn't affect high RPM stuff, aside from at the very peak of their ability that you lose with lower pressure.. With lower pressure though, pulse width will have to be higher, which is better for larger injectors that might not handle low IPW so well. Yours will be fine either way.

 

Ok, so I'm thinking about ditching the stock fpr for an aftermarket one that's vac/boost referenced. I already have the fitting that goes to the feed fuel line and the one that goes to the fuel rail. But I need the one for the return. Does anyone have a part number? And a recommended fpr.

 

would this be the one for the return line?
Russell Performance 644020 - Russell Fuel Rail Fitting Adapters - Overview - SummitRacing.com

 

Looks like the one I posted is for the supply which I already have. I believe that I need a 5/16 fuel line disconnect. The only one that I can fine is Aeromotive #15103 and cost about $35. So much for trying to keep a budget. lol