I put some cheapo autolite spark plugs in the car today because they are a step colder than the stock temp ones. It seemed to completely eliminate the hesitation I’ve been feeling when the car is already warmed up, but I haven’t gotten to put many miles on them yet. I’m really interested to see if it’ll help with the cold start issue the car has been exhibiting. I should know more tomorrow sometime. Eventually I’d like to get a better set of plugs in at this temperature, but this is all I could get my hands on today.
If you’re interested to know what the temperature of a plug means, wikipedia has a pretty good section on plug heat range.