<VV> Is it vapor lock

[Chris C, Warwick RI]

The patient:  63 monza 900, pg.  Stock motor, no mods.  Drives better and 
better each week.  Have been taking longer and longer drives.

The symptoms.

95 and pretty muggy.

Drives nice to the cruise.  Go to back it into my spot.

Stalls.  It never stalls.

Very windy, feels 15 degrees cooler (6 miles away).

Push it the last 4 feet (ever feel like everybody is looking at you).

Check the carbs.  Move the linkage and small drops from the right 
carb.  None from the left.

Check the clear in-line filter.  It has gas.

2 hours later, the engine is cool, and she starts up and drives like 
nothing happened.

Freek incident, vapor lock?

Anything I can do to avoid it.