Quote Originally Posted by Driver50x View Post
Hmm, that's interesting. Back in the eighty's I remember lots of guys putting a piece of cardboard in front of their radiators during the winter. I always wondered why that was necessary. Maybe it was because of the poppet thermostats everyone had. It was worse with pickups than cars. Pickups had very small heater cores in those days.
In Idaho I would do it just so that the heater would work faster. I also had a toggle switch wired to the AC high idle solenoid for warm up on cold mornings. But then, I was seventeen and didn't know how retarded I was.