My 225 slant six is hard to start when it's been sitting for a day or two. I crank & crank & crank, pump the pedal and she finally starts. Running stock 2bbl setup with 2" exhaust and orange box ignition. New tank and mechanical fuel pump too. It runs great after initial start. It did the same with the 1bbl setup too.

Orange-box ignition probably isn't causing your problem, but it's likely to eventually cause you problems (not a good/reliable setup). HEI upgrade is better.

Hard starts: The correct cold-engine starting procedure is to press the accelerator to the floor once (you should hear a "Click!" from under the hood as the choke plate closes), then take and leave your foot off the accelerator while you crank. If that's what you're doing and it's still hard to start from cold, first make sure your choke works. Even if all the parts work when you take off the air cleaner and look, sometimes the air cleaner can get in the way of the choke plate closing when everything's installed.

Next, make sure your manifold heat control valve is working correctly (yes, this can affect cold "next morning" starts), make sure you've got a thick, heat-insulating gasket between the carb and the intake, and do the Fuel line mod.

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Too many people who were born on third base actually believe they've hit a triple.

I have no idea what temperatures you experience in Grass Valley, but here in the Texas summer heat, the gas in a carburetor will evaporate in two days and require quite a bit of cranking to refill it.

Late fall, winter, and early spring are no problem, but I've learned to live with carbureted car's summer starting problems. If I could tolerate the noise of an electric fuel pump, I'd go that route.

Here is a wiring/equipment concept for a fuel primer.
http://tinyurl.com/omr4hbw

Once installed in my 65 Dart with Super Six I'll let you know how it worked.
Right now I have the same gas disappearing act after a few idle days.

The idea is to only use to prime whether it be the result of sitting idle for an extended time or other gas lacking event.

Push button switch will be a used wiper switch mounted at the cigar lighter location to trip the relay.

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1965 Dart 110k, 225, Carter BBD Super Six, 2 1/4 single exh., sbp manual scarebird front disc, 7 1/4 rear 2.94 sure grip, 14 x 4.5 OEM wheels, 833 OD with hyd. throwout bearing, HEI, electric fan, ram air/heated air, Accusump. http://plymouthcarclub.com/