[LeanBurn]

I wouldn't mess with a bottom grill block on that vehicle. Since the upper grill is smaller the vehicle gets most of its cooling from the lower grill anyways and you deprived it of that. You still need to have everything function correctly for cooling and performance especially turbo engines. So how do you know the engine temps were a little higher...by the dash gauges or by a scangaugeII? Dash gauges are notoriously inaccurate.

I would look to do an upper grill block and look at other avenues like a belly pan, pizza pan wheel covers.