Related Photo Galleries
27 Here are fuel pressure and return lines at the back of the Holley Avenger EFI throttle body. The large 3⁄8-inch line is pressure while the smaller 5⁄16-inch line is return to tank. You can hard or flex line these connections. The return line must be a minimum of 5⁄16-inch and no more than 3 psi fuel pressure.