Engine Hard Starting After Days Of Rest

Lord Sparky said
1967 440 Magnum, 600cfm Carter carburetor, electronic ignition, manual fuel pump. Engine was just tuned up with all new filters, wires, plugs, rotor, etc. Runs great once started. Battery good.

The next day after a drive, the engine starts right up with one pump of the gas pedal. Same with day two. Day three, takes a little more cranks of the starter. After that, I might have to start the engine a second time to get it going. A week later, can be much more difficult to start.

Is hard starting caused by evaporation of gas in the carburetor? Does anyone else have this issue and have some tips? More pumps of the gas pedal?

Yes fuel evaporation. Edelbrock carbs seem to be prone to that. It could be because of the float bowls being part of the carb base and absorbing a lot of engine heat. A electric priming pump, a fuel return system and carb insulators all help.

RustyRatRod said
My truck (75F250 351M) had an Edelbrock 1406. Did the same thing. Now it has a little Street Demon 625 three barrel. It can sit for a month and pop right off with several pumps. So I don't know. It might be fuel evaporation.

It sees the Holley design carbs are less prone to fuel evaporation. It could be because the float bowls are isolated from the carb body and I imagine even the bowl and metering block gaskets help insulate the fuel from the heat.