Hey all, thanks a lot for the suggestions. I have checked the speedometer (and odometer) against a GPS, and it’s pretty much spot-on. I also just checked my spark plugs, and there is some black sticky-ish residue around the edges — photos attached. Does this indicate too rich a fuel mixture, or oil leaking into the cylinders? If it means too rich, then sounds like maybe I just need to drive with the GAV more closed, which I’m sure would give me better mileage — but also feels very underpowered, so then I’d wonder if that indicates a different problem? Doesn’t seem like anything’s dragging, at least not severely, as it rolls downhill pretty freely.
Where I drive (near Salem OR), it’s not mountainous or high altitude but it is somewhat hilly. I’d say the ground covered on my drives is about 50-50 flats vs rolling hills. I will try doing a flat highway test, as nkaminar suggested.
J Franklin: when you say the Model A likes 35-45mph for best mileage, would that mean driving pedal to the floor with GAV closed (or maybe 1/4 open), which would translate to about 40mph in my car, or driving with the GAV more open (like 1/2) and less foot on the gas? I’m guessing the former, but this is something I’ve always wondered about.
Thanks!
