Sorry, I stopped putting my name in my signature for a while because nobody got it right anyway. It's Josiah.

I'm willing to admit my mileage could be a heinst worse than what I claim. I haven't verified the accuracy of my odometer. I should probably get a GPS unit.

I don't advance the timing very far, I just played around with it a lot and found that my engine likes it a few degrees advanced. I am also running a rebuilt dual point distributor so I can keep the dwell and timing pretty well controlled.

I am indeed running a leaner jet- I have a 261 with a mongrel "B" carb made up of parts from a 216 carb, a 250 carb, and a 261 carb. I can't remember what jet I used but it wasn't the one from the 261. I arrived on the value by reading the plugs until I got a nice brown color after a long drive. I'm also running the valves a bit on the loose side of spec, which lowers the overlap a bit and acts like a smaller cam.

As far as it running too lean- it isn't. It behaves nicely on long drives, doesn't surge or buck on deceleration, runs 180 all the time, and the valves haven't receded into the heads. It has been burning oil lately, though, I have bad valve guide seals.

I also have plywood for a bed and have an alternator and an electric fan (no mechanical). Don't forget that the 3/4 ton trucks weigh a bit more than the half.

Whatever your mpg is, as long as you are happy with it it doesn't matter. I think it should be at least 10.

I'm getting ready to overhaul the thing and put in a Jimmy 302, though. That should kill my mileage.

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A lone amateur built the Ark. A large group of professionals built the Titanic.