1976 300D ho-hum fuel mileage

Car is getting 20-23 MPG and can not seem to get much improvement. This was the mileage when I started, and have since adjusted the valves (nice wrenches, Kent!), changed the fuel filters, replaced all fuel lines (they were hard and looked leakish), installed Monarch nozzles set to 1620PSI (great kit!). After all of that, it runs like a dream with not much smoke, but still the same ho-hum mileage.

I tested an injector before I cleaned, re-sealed and installed the Monarchs. It popped at about 1400 and shot a straight jet. After cleaning, sealing, shimming and installing the monarchs, they all pop at 1620 and shoot a nice smokey atomized pattern. I was sure this would do it, but there was virtually no change other than in smoothness.

I do notice some fuel seepage on what looks like a pressure regulator on the main fuel filter, but it does not appear to be much. Do you sell these?

Other thoughts?

Thanks for your help.

-Dan

Forums

Chassis Model Number