I bought these fans for my built in 406 SBC in my Chevelle which always got hot at 210F and was running 230F when hitting the car with a plastic covered 5 blade clutch fan. I first replaced the 2-wire copper heatsink with a 3-wire aluminum heatsink, but the machine was still overheating. I then bought these fans and now the car goes to 190 and 210 when it's hot outside and I've started the car. These fans solved my problem. A very well made cloth. After installing these fans, there were noβ¦