GM 99-2014 Fuel System info
GM LS Swap Fuel System info
GM used two fuel systems,
- double line or return style fuel system on the earlier models that use a vacuum referenced fuel pressure regulator on the fuel rail, you can use any fuel pump with a minimum pressure of 60 psi in your application.
- Singe line or constant fuel pressure fuel system on the later GEN 3 and all GEN 4 (2007-2014) models that use a fuel pressure regulator that is part of the in-tank fuel pump or a variable speed pump on some GEN 4 trucks. If you have this one, you need an external fuel pressure regulator set at 58 psi or a 'corvette style' fuel filter/regulator in combination with a fuel pump that supplies 60 psi minimum.