I saw no temperature changes with either my temp or permanent grill blocks on my Cavalier. This is due, no doubt, to the huge opening between my bumper and radiator. Closing that hole is the next aero mod on my list.
Speaking of warmer engine temps, I finally got fed up with low temps this winter, and took action this morning; I covered about 2/3 of the radiator with cardboard, leaving it open in front of the fan. I had been running 130-140*F on the highway, but I ran at thermostat temps of 180* both ways today. Yea!
And I'm running at cooling fan temps of about 204* when I get off the highway. Now I really want to get my 195* 'stat installed...
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