[DeTomaso] Why is it hard to start cars that have been sitting for months?

[Charles McCall]

Charlie,
I have never had an engine that does as you describe.  I don't think its
carb. I also observe that modern gasoline doesn't seem to varnish like it
used to.  All I find these days is a fine power residue.  I have allowed my
Holley, and my Webbers, and my snow blower, and my backhoe, to evaporate dry
several times without any issue other than re-filling the float bowls.

I wonder if you're getting some valves hanging a little open after long
storage.  Do you get any lifter tapping while it is running poorly?
***Thanks Tony!
I didn't notice any extra tapping. I have solid lifters so I have a little
clacking going on anyway. In an enclosed garage, the exhaust note of the
Pantera could drown out lifter tapping anyway? 

Anything one should do to avoid valves sticking if the engine won't be
started for months?