Quote Originally Posted by MetroMPG View Post
My '14 Mirage has a full upper & partial lower grille block.

I just drove it for nearly 30 minutes after a cold start at -20C = -4 F, and the engine never quite got up to normal operating temperature (low 190 F range). The highest I saw was 183 F (ScanGauge II).

If I ran the heater fan on the highest setting, the temp actually dropped a few degrees, to the high 170's.

Now, this all happened under pretty efficient conditions: mostly level country road cruising at 70-75 km/h = ~43 mph, which is not very demanding on the engine. It wasn't quite generating enough "waste" heat to keep up with the heater.

An automated variable lower grille block would have helped. I wonder what the oldest & most common cars are that had this OEM feature... might be able to scavenge parts at a junk yard.
I actually considered trying to produce one of these but the biggest hurdle is the Return on investment period is very long. As you may have noticed from other forum threads like https://mirageforum.com/forum/showth...=block+melting 3D printing isn’t ideal for a year round grill block. Laser cutting metal is very expensive. The alternative would be to either remove it in the summer or try materials like chloroplast. My other concern would be how to mount it at highway speed it’s under a **** ton of load when closed I’m not overly confident in how I’m going to affix this to the bumper. alternatively I could do what Volvo does and do an automatic grill block infront of the radiator instead of mounted on the grill. My other concern was that I have no idea how large of an automated opening id need. ideally I’d do the entire grill opening but that’s pretty large and would be complicated. Overall unless you are somewhere super cold the benefit is mostly limited to the first few minutes after startup. A block heater would probably be more simple and economical. I spend under 60 a month on gas the roi for me would be in the years. If I had a large YouTube following I’d consider taking on a project like this. Another alternative to this would be to try and do a smooth chloroplast engine bay underbody for aero and to maybe help retain heat. I was also wondering if closing the gap between the hood and the cowling(windshield) would have a similar effect to a grill block as it would stop some of the flow of air over the engine. (Air won’t enter the engine bay if it has no where to go?) not sure how that would effect aero though