1988 Iroc Z 305 TPI can anybody identify the fuel return pipe.
Also minimum fuel pressure at Schroeder valve.
What should happen if I clamp the return line. Trying to check regulator function.

 

The smaller one is the return. Ideally fuel pressure at the valve should be 43.5psi, if it doesn't get close to that when running you might have a problem. Pressure should climb and hold if you clamp the return.

 

thanks will try that today

 

On standard 305 TPI do you guys run the standard fuel regulator and just change diaphragm as required

Thanks

 

I tested fuel pressure at idle 38 went to 90 with fuel line clamped
Left clamps on after 40 mins pressure was still at 80 so guess that is holding. Have new injectors coming from Southbay.
So what do people think about fuel pressure. Dropping tank big job.
Still chasing intermittent poor idle as per my previous posts.
Thanks
Gary

 

Sounds like your fpr is functioning within spec.

 

what do you think of fuel pump readings

Has anybody cut access hatch in convertible for fuel pump

 

I would go to say your fuel pump is ok. Not too sure about the convertible part, but a lot of people have cut the hatch. If you decide to do it, please do it right! Buy a hatch, measure twice, cut once. It will make your life easier down the road, BUT you are cutting up your car.
I dropped the tank on my car, and the only difficult thing about it is the factory tank filler neck is solid and extremely difficult to maneuver out of where it is supposed to go. Other than that, not much of a fuss.

 

Agreed. There is no need to cut the floor since the fuel pressure is correct.

 

thanks gents

Only thing left is the injectors when they arrive and also I am removing an aftermarket alarm that is playing up. It appears to cut the fuel but not sure where it does that. Car ran the other day with the alarm going off.
Does the ninth injector cause any issues and should it be removed.

 

Keep in mind that fuel pressure needs to be measured with the vacuum line disconnected. This simulates WOT conditions inside the manifold, and it's where/when it's most important to have proper pressure.