Hello Covarxi,
Tks for yr answer. What I understood is:
1. There is a gain due to reaching work ideal temp faster.
Comment: This is very important if when you use the car in the city with short trips, and in the road with cold trips.
2. There is a gain due to better aerodynamics, as the avoid air penetration and turbulence.
3. Ther isnīt overheating of the engine.
Comment: for temps lower than 25 grades Centigrades we may say for sure.
25 degrees is the maximum here.
Anyway, in my first travel I will use the car for some km with the grill cover and some without it, to compare. Will put it to work say at 100km/h cruise controlled. Then at 70km/h for comparison. Will write down fuel yield results. Here we measure it in km/lt.
Of course will keep an eye on the temp.
Will share results here.
Saludos,
OLdBeaver