If you tow a car on and open trailer in 28 degree weather for one hour, then stop and try to start the engine within 5 minutes will it be harder to start than it normally is compared to just sitting overnight in the same 28 degree air?

Car was last run the day before so nothing wrong with the car, and the carb has fuel in it.

Carbureted 318 electronic ignition. Don't try to diagnose a bad battery, cold starting problem, and rotor phasing, et al.

No, cars don't feel wind chill.

Wind from towing may get the "core temperature" of the engine down to 28 degrees a little faster than just sitting. Still, at 28 degrees, it should start just fine.

If I may ask, what is the problem? Did it not start?

Assuming the car was already at 28º before you left, then it won't get any harder to start once you tow it for an hour.

Overnight low was 23, I towed from 9-10AM. Was still cold out. I'm 2 hours from Canada, sunshine doesn't do much this time of year. Car was hard to start, but started and ran good as usual while driving.

Car is for sale guy used the hard start as part of the lame excuse to not spend money.

Doesn't wind chill affect water? That's why carburetor ice up from the airflow in cold weather?

I use to have one of the pocket wind chill charts we used in the U.S Army in Germany, I seem to remember that a 40 MPH wind would lower the wind chill factor to down around -30 F from 32 F
All air cooled airplane motors have carb. heat to prevent the carb. from icing up in flight and quitting

inanimate objects do not feel "wind chill"

like mentioned, 'wind chill' only applies to things that can sweat. The evaporating moisture from sweating removes a lot of energy, making the sweating object colder than the ambient temperature.

Towing it will help it cool off quicker, but it won't go under the ambient temperature. Unless you were spraying water on it and the RH was low enough that it was evaporating and not forming ice :p

Carbs icing over has to do with the temperature, RH, and dew point, IIRC.

reminds me of that old wives tale that you should not park/point the front of your car (the radiator) toward the North overnight cuz the cold northern winds will freeze it up easier (from the WC)