Im trying to find out what the gph is on the stock fuel pump in my 1987 Camaro IROC-Z 305 TPI. Im installing a fuel pressure regulator and im having a few leak issues. I have an installation chart refrencing the gallons per hour flow from my stock pump to what I will require for size in my return line. any help identifying what the flow rate of my fuel pump would be???

 

TPI 5.0L and 5.7L fuel pumps need 37 psi to 43 psi. A 5/16" return line would work fine for your IROC. I used a 5/16" when I did the 1989 IROC 5.7L 350 swap in a 1985 c-10. No problems on rerturn line.