Here are the the facts from all the testing been doing.
1. FORD said in Hotline Assistance Request that The Approx. engine Operating Temp should be 202-212deg.F
2. The best MPG temp range is 202-230deg.F
3. Starting with cold ICE and outside temp from 37-70deg.F driving hwy loop of 14.1mi you gain average of 4.MPG with Grill Covers on vs off.
4. 3-4MPG gain city driving. The Grill Covers heat up ICE quicker and keep it warmer than without Grill Covers. There is about a 30-40deg.F WT difference with Grill Covers on and off. Even at 70deg.F outside temp I could only get to 200deg.F occasionally and most of the time 180-190deg.F. range.
5. The Grill Covers really helps short trips 3-10mi because of short heat up time for ICE. Adding oil pan heater improves MPG's another 2mpg.
6. Because shutters open when the CMAX is stopped Grill Covers keep ICE warmer longer than without.
As more people get experience with Grill Covers we will add more Post.
Edited by ptjones, 21 January 2014 - 03:25 PM.